Pros: Where to start? It looks very sleek and slim. Its a full size keyboard with number pad, but substantially narrower than my previous keyboard. The reciever is tiny so you can hide it away on your desk. (It even comes with a cord to plug the receiver into if you're like me and have your tower several feet away from your desk.) I can't say enough about the backlight; now that I have a backlit keyboard I can't type on anything but! I was a little hesitant when I purchased it beacuse it said "10 days" battery life. When I was using it several hours a day, I still managed 2 solid weeks on a full charge (I alawys shut the backlight off when not needed, and also shut the keyboard off when I walk away.) Lately, I have been using it about an hour and a half a day and have gone more than 2 months on a charge!

Cons: Price is a little high for an RF keyboard, but the backlighting and fantastic key feel make up for it. I DEFINITELY miss having dedicated media buttons at the top of the keyboard. I used them all the time on my old keyboard and miss them quite a bit.

Overall Review: Overall, I'm very satisfied and I don't doubt that you will be, too. Keep in mind that it is still RF wireless, not bluetooth, so you aren't going to get 30 feet of range out of it.

Pros: Rechargeable via micro USB Normal key layout with regular sized insert and delete keys. Able to replace with normal AA batteries on the fly Small Unyfying wireless connector The keys have a rubbery look but they are plastic thats slightly concave and rounded off smooth White backlight, not red or the overly used blue that cause so much eye strain All keys light up, this is a huge plus when compared to the wired version where only the amber function keys lit up and not the F keys Has 4 brightness settings and an off setting and the highest setting is brighter than the corded version No lagging so far, im currently playing COD4 with this, no issues yet. Setpoint can disable the annoying keys like CAPS, insert and scroll lock. Windows key and numberlock Only the CAPS has a small dedicated green light on the key that lets you know its on. Its about the exact same length and width as the wired version I can boot into the BIOS with this keyboard no issues.

Cons: Back light turns off in "less than 3 seconds" after your hands leave the keyboard. The hand sensors are located in the palm rest, 1 to 2 inch proximity required to activate backlight. To remove the battery cover, you have to warp/bend it, then slide it off Comes with rechargeable EniTime 2000mAh 1.2V batteries. Not Sanyo Eneloops! To remove one of the batteries you have to rip off a hard plastic sticky tape thats tough to get to. Every time the computer is turned on the brightness setting resets to the lowest level No AC wall outlet to USB adapter included like the Performance Mouse MX. Font looks too fat, the symbols on the number row is basically right on top of each other. The battery life key "function F7" does not bring up an onscreen display of the battery life, it just lights up the battery meter on the keyboard. The battery level dropped to 1 bar in 2 days of regular use with brightness on max, keyboard was always on, hit critical red in 10 days .

Overall Review: I upgraded from the wired version for the wireless and rechargeable benefit. Its great and so far i like it, no major complains yet. The font on the wired version was way better and sharp, its like someone turned on "bold" on these keys. The wrist rest is a hard piece of plastic, not like the soft rubbery material on the wired model. It was an upgrade but not without a few drawbacks and nothings perfect. I will also be switching out the batteries for some 2000mAh Eneloops. Another note is that to charge this you must use USB connection, for those that have a modern phone or any micro USB charged device made in the last 2 years you wont have to worry about the keyboard only charging when the computer is turned on, i use the charger from my Performance Mouse MX thats plugged into the wall, not the computer. Reception is great at 10 feet, and no issues syncing the keyboard with the Performance Mouse MX unifying receiver i already had The keyboard does not pass data over the USB cable

Pros: Very comfortable keyboard to use. Nice fit and finish. Sleek. The shape and texture of the keys is great, and the backlighting is gorgeous. Calculator key is great for the engineer! Dedicated volume/mute keys are great for the HTPC. Great reception/range, after troubleshooting! See below.

Cons: Reception was an issue but it was solved. I have two of these keyboards - one for work and one for home, along with a pair of Logitech Anywhere MX mice. I had one set at work originally, and liked them so much I bought the same combo for my HTPC build. On my HTPC build, the range was non-existant. I could sit 2 feet from the PC/receiver, and the mouse and keyboard would drop out every couple seconds. At work, they had great range, 15 or 20 feet. I swapped my work keyboard/mouse with the new set from my HTPC - same issues. On a whim I tried the USB extension cord that comes with the K800 - and it fixed it completely. Perfect reception from across my apartment, where before I could be a foot away from the receiver and it would drop. I tried the receiver in the front and back of my case, multiple USB ports, all of which had issues. Physically moving the receiver away from the computer solved the issue.

Overall Review: I'm not sure what about my HTPC combo caused this - the receiver at work is plugged directly into my laptop, and I've used the mouse on my desktop the same way - no issues. Only my HTPC had this problem. Perhaps the all-metal case? Or the compactness of the HTPC build caused to much noise near the USB ports? Here is my HTPC build: Case: Lian Li PC-C37B Mobo: MSI 890GXM-G65 CPU: AMD Phenom II X4 840 PS: Antec Earthwatts Green EA-430D Memory: Mushkin Enhanced Silverline 2x4GB DDR3 1333 HDD: Samsung Spinpoint F3 500GB HD502HJ Wireless: Linksys WMP600N Optical: Samsung Black BD-ROM SH-B123L Graphics: 2x Sapphire Radeon HD5570 100293L OS: Windows 7 Pro Display: Samsung UN46C6300 46" LED backlit TV There is also a cable box nearby as well as a surround sound system, but the receiver is currently relocated closer to the TV, cable box, and sound system and reception is perfect. The issue was certainly related to being close to the computer itself.

Pros: Good typing feel (if you like slim/ laptop), responsive, nice looking, wireless (kinda, see cons) but still backlit.

Cons: I got this to use as a wireless keyboard, but it requires a USB cable to recharge. This means you do need to keep a cable around, and no option to swap batteries. The battery life seems decent, and there is a cover on the bottom with a screw, I assume if I can replace the battery in a few years if needed. Disappointing, but on balance not enough to knock a full egg off. Um, I guess if you want to store it upright you can't charge it the same time, not an issue for me.

Overall Review: Backlighting seems good to me, but I've nothing else to compare it to. If you're looking for a standard / old school keyboard this won't have that feel, because of it's slim design it's more like a laptop. It's designed to be stored upright if you want, which I thought was cool, but nothing I need. I bought this to work with a 'unified' mouse I already had, needed to download an easy to use config utility to get them to work with one receiver. Again the need for an occasional cable charge makes 'unified' seem less worthwhile. I don't use the macros/shortcuts, so no feedback on them.

Pros: I can't believe this thing's lasted 3.5 years since purchase. The backlighting is useful without being too much, the keys have nice action, it's full-sized but not too big for your lap. It's not really billed as a gaming keyboard, but that's what I've used it for, and it has performed perfectly until this week. Purchased March of 2011.

Cons: There is no numluck indicator. There's a capslock LED, but nothing anywhere on the keyboard itself tells you if numlock is on or off, which mystifies me. A minor annoyance, and the only design choice I have an issue with. Their tech support is told to upsell you instead of providing useful info. I left a bad review and nearly gave up on this thing, based on a useless convo with a useless tech.

Overall Review: Wish I could edit my original review. Short form for the potential buyer: This thing lasted through 3.5 years of heavy gaming and light abuse. The batteries still hold a charge for days. The backlight is still as good as when it got here. I've never had it drop connection - less of an issue on keyboards, but still. This week, the W key fell off. No pop, it's just loose now. It looks like the tiny pins under the key are finally too worn down to hold in the sockets. If I type too fast it goes flying across the room. This is the *only* failure this keyboard has experienced, and it took over three years. Chances are, if you're not a keyboard-mashing heavy gamer such as myself, it might last you even longer. I'd say get it. Background and a note about cleaning: A few months after purchase, this keyboard took a spill. Soda, too, so nasty sticky-dry gunk. I called tech support to ask how to clean it. I was told, "you can't, you'll break it, here let me give you a coupon for a discount on a new one." Obviously (to everyone but Logitech management), that didn't incite me to throw away my 5-month-old keyboard a buy a new one, it just !'ed me off. Fortunately I decided to ignore the tech and try cleaning it. The battery cover holds a couple of AA-form-factor rechargeables; undo the screw, open as normal, set batteries aside. I then just rinsed the whole silly thing under cold running water for a few minutes. Really. Not hot, that can lead to mineral build-up. Give it some pressure and time, and even dried soda will rinse out under cold. Afterwards, i cloth-toweled it off (no paper!), propped it up sideways in a warm part of the room and let it air-dry for around 30 hours, before putting the rechargeables it came with back in. It worked perfectly, has ever since, until this week. So you can clean it yourself in the event of disaster, but do so carefully: think it through, nothing that will leave residue or bits of things in the works, and give it plenty of dry-time. I'd hate to penalize the engineers that designed this monster just because their tech support guys were given stupid scripts, so I'll be buying another, and here's to 4 more years. This keyboard's restored my faith in Logitech's quality and durability.

Pros: Simply amazing. Incredible battery life (charge maybe every 3-6 weeks). Light brightness can be adjusted easily. Caps lock and battery life indicator. Wireless distance is great, comes with mini USB transceiver. Keys are quiet and still work like a dream after a year of constant use. Feels sturdy and well build, not cheap. Overall Slim - Wireless - Long Battery Life - Illuminated - Amazing

Cons: None whatsoever.

Overall Review: This thing is a beast! Spilled almost an entire bottle of Water onto the keyboard and after literally POURING the liquid out of the keyboard and letting it dry out for a few hours, still performed like new with no problems. Would not choose any other keyboard. I was amazed.

Pros: I've been using this keyboard as a HTPC/Gaming PC keyboard for over a year with absolutely zero issues. The back lighting is fancy, the keys have just the right feel to them (typing anything is a treat), and the battery lasts a very long time! I like the calculator button, and the sleep button (FN + F8) is really convenient for an HTPC setup! But the best thing about it? The customer service! Since I use this keyboard on the couch, dropping it on the floor is always a potential hazard. Recently, it fell so hard into the corner of my coffee table that a key broke off. I called Logitech to purchase a new key and instead they are sending me a brand new unit! For free! And I don't even have a receipt!!! That right there should negate almost every bad review about this device. I'd give more eggs if I could!

Cons: Uses the same frequency (2.4 GHz) as a lot of other wireless devices such as wireless routers. Not that I've had an issue with the keyboard, but I share the same tiny USB receiver with a Logitech Anywhere MX mouse (also love it) and noticed severe lag issues with the mouse until I changed the channel on my wireless router - now everything is PERFECT. I would assume everyone who says not to use this for gaming or that it's not very responsive is probably only dealing with this very simple problem. So not really a con if you can figure out how to change the channel your router is broadcasting on.

Overall Review: I've read a previous review about bad battery life, and that is just not true. I've had this keyboard for almost 2 years and I've had to recharge it somewhere around 10 times. I'm in the habit of switching it off whenever I'm not using it, and that seems to be working really really well.

Pros: 5 phase illumination. Full sized keyboard w/number pad. FN function keys. On/Off switch. No slide bottom and Feet Unifying Receiver

Cons: The only con for this keyboard is you didn't buy one yet.

Overall Review: I have owned this keyboard since 2010 and have had to change the rechargeable batteries once, about three months ago. Other than that this keyboard has been in constant service and has never failed to provide excellent service.