Pros: everything.

Cons: None

Other Thoughts: Not a fan of flat keyboards, so kinda weird getting used to.

Pros: I upgraded from a Logitech G15 , which by comparison was much wider and slightly more narrow height-wise. I'd been using that keyboard since 2007 though so you can probably take everything I put here with a grain of salt! This is my first mechanical keyboard so I can't really compare that aspect to others but a few things I've noticed:

-The key shapes take a little getting used to but overall feels better than normal keys once you do.
-I didn't think I'd like the LED keys as much as I do and, doing graphic design on my own hours, just having the lights out and seeing all the keys lit up with the colors I gave them makes me smile for some reason.
-The keys themselves are very punchy, which I understand is normal for most mechanical keyboards, and I know some people complain about the noise for mechanical keyboards but this one is only slightly louder than my old G15 and its weird rubber plunger things.
-With Windows 7, having used other logitech mice/keyboards, the Logitech Gaming Software program instantly recognized this keyboard as soon as I plugged it in and let me begin customizing it almost immediately.
-I ended up not even noticing there was a volume bar above the keypad until accidentally brushing over it, but it feels nice and can't be accidentally cranked up to ear-blasting levels unless you really try.

Cons: -Conversely to my old G15 which had a keypad's worth of buttons hanging off the left side (it was the blue version), the G-Keys on the G910 are few and sort of in an odd spot. The space between them and the shift/capslock/etc. keys aren't big enough to fit your finger between, which means when I blindly go to press control or shift I end up hitting one of the G keys since I came off of a somewhat longer keyboard.
-The height of the keyboard makes my fingers hit the roof of my keyboard tray if I don't pull it out; it is noticeably thicker than past keyboards I've used with the keys rising up a ways. They feel nicer this way but it makes using the tight space of a keyboard tray annoying unless you're not opposed to just setting it right on your desktop.
-Like the above, using this in a keyboard tray means you aren't going to be able to use the ARX slot at the top of it, I have yet to do much with it.

Other Thoughts: Overall I'm very happy with my purchase, especially since this was on sale ($139-$149 + a copy of The Division as opposed to $179). It takes a little getting used to but overall it was a much needed upgrade personally. The only other thing to really note is, as many others have pointed out, there are about six tiny media keys in the upper right of the board that are unalterable blue, I didn't notice those at first, I still barely notice them at all.

Otherwise, great keyboard, would recommend, still a fan of Logitech.

Pros: I was nervous about purchasing this keyboard after some of the reviews....but the keyboard ended up being fantastic. The ridges around the keys are not nearly as pronounced as they seem in the pictures. This thing took me all of a minute to get used to. I had a Corsair Limited Edition K70 I was using...now I've switched to the G910 and notice no difference in performance, but now I have extra keys and the RGB colors if that excites you :)

Cons: Doesn't recite poetry

Other Thoughts: I think this is a solid option for any hardcore gamer(I play apprx 2500hrs a year gaming)responsive, unique, extra keys for macros as well as the multimedia keys. I would recommend this keyboard to anybody as logitech has created another excellent product with software that is super simple to use.

Pros: Keyboard has a lot of customization options in terms of macros and lighting.
Integrates with a mobile app and display some handy info on your phone or tablet, I hope developers use more this feature in future games.

Cons: 1- The most annoying thing I found in this keyboard is that the NumLock will be always disabled when the computer is turn on from a shut down state, I used to have the Logitech Wave keyboard and this never happens, I saw online that the only way to do it is changing some registries which I don't want it to do.
2- No Shut Down/Sleep Key, with so many keys this keyboard has and there is no Shut Down/Sleep key? Some people like to shut down the computer with a single touch of a button.
3- The bigger palm rest that is included should has had some sort of pad not the hard plastic like the smaller one.

Other Thoughts: The cons above make me remove one egg but definitely I would recommend this keyboard.

Pros: -Individual key RGB backlighting capability!
-ARX Dock for app development!
-Ergonomically shaped keycaps (more on this later)
-Amazing aesthetics!

Cons: -Not really a con but:
Logitech's site did say that they sculpted the key caps individually to provide maximum strike area or something, but I didn't realize how big of an effect it would have until I used the board for the first time. At first, I actually kind of hated the scalloped keys. Never enough to return the keyboard because I liked the rest of it so much. Now, I've gotten used to the feel. I still hiccup when I type fast on it now and then, but this is really user error, not really a fault on Logitech's part

-I feel that Logitech could put more work into making the gaming software easier to use and get around. It took me FOREVER to figure out how to do per-profile keyboard lighting correctly, because it would sometimes work on launching games and sometimes not. Another thing is that the software has a bad history of deleting your profiles that you set up if not run as admin or something stupid. Logitech has addressed this issue and I haven't had issues since, but still.
(note)
Not all of the gaming software is bad. The part where you assign the G-Keys their macros is actually really snappy and works extremely well. Kudos to Logitech for that (looking at YOU, Razer Synapse)

Other Thoughts: If you want the best of the best and looking to be loaded out with everything Logitech like I do, then this keyboard is a good choice. It does take getting used to the keycaps, and you may not even be able to stand them. However, I've used this keyboard alot for both gaming and programming, and it is now a dream (minus the hiccups) to work on.

The key lighting capabilities may leave something to be desired (you can't save different custom keylighting states on the same profile, its either that or nothing) and weird nuances with the software for all of Logitech's gear in general. But in regards to the keyboard itself, I really like it alot!

Pros: Just got this today, so...this is an initial impression.

Pros are:

-It feels great. Keys are matte finish, which I love. My last keyboard had glossy keys, witch was the only thing I didn't like about it.
-The lighting effects are spectacular. The keys really show up in a dimly lit room. Very clear and crisp.
-The key action is superb. You barely press a key and it actuates. Amazing in games where time and timing matters. Actually a little hard to get used to typing, such a fast response time, but I'm working on it.
-The software, simply amazing. You know the saying, " Describe it to me like a 4 year old"? That's how this software works. A four year old could program this keyboard. That's a good thing. Really good thing.

Cons: Cons are:

-It comes with two wrist supports, which is great, but they don't connect securely, so there's a rattle sometimes, especially if you have sweaty palms and it sticks to your hand a bit. Not a big deal by any means, but I don't like rattles. Otherwise, the wrist supports do what they should and are comfortable. It's also nice to have 3 choices, large, small and none.

-It's expensive. No way around that, even on sale as I bought it, it's expensive. Worth it? Time will tell, and by time I mean years. My last keyboard was a Microsoft Gaming Keyboard and is over 5 years old and would be going....but I bought this. Microsoft doesn't make hardware anymore and there were deals to be had. So, if this makes it 5 years...yeah, worth it. We will see.

Other Thoughts: Some odd bits:

-It's the heaviest keyboard I've ever seen. At some 4-7 pounds, it's not gonna slide anywhere.

-Some people have complained about the key face shape. The left half of the board is different from the right, which is odd. Thing is, this board is made for gaming, not transcription. The reason it's that way is so your right hand knows when it's left the gaming area (or at least the most common for keybinding). As such, it works and I personally like it.

-The lighting and its many variants (which you can download an SDK, if you so fancy and write your own) is really amazing, so worth mentioning again.

-For, me, as a novice with the board and not the best typer, the minuscule distance the keys have to travel to activate means I'm making heavy use of backspace currently. A pro typist probably wouldn't.

-If you like clicky and clacky keys, this doesn't do that. It's not cherry switches, Logitech made their own. To me, they are pleasantly spongy and quiet. I prefer they be quiet.

Pros: Good quality switches.
Lots of customization
Great app Support
Phone holder!
Bright LED's

Cons: Customer service is by far the worst thing I have ever dealt with. It was said you would get Tom Clancy's the Division for free with purchase of one of there newer keyboards. Went and got one the day I saw the AD because I was due for a new keyboard. I have contacted customer service they asked for information the receipt and even picture of the keyboard and box. But the service person replies every 2-3 days after I sent information to him.

Other Thoughts: Great product overall but customer service is the worst. If I did not have the problem I would gladly give them a 5/5 because its a solid keyboard.

Pros: This keyboard is fantastic! the key feel is a tinge firm but I prefer it that way. Many people have been having trouble with the software on Win10 but I have had no issues. the lights are great and I LOVE being able to individually program the color of each individual key and there's no color bleed, it makes finding specific keys simple and quick. (I keep my J and F keys a seperat color from the rest as a visual reminder to where my hands belong among other color cues for many other keys.) Light on/off button is a nice feature and media controls are right where I like them.

Cons: The key press is LOUD! This isn't a problem for me unless I'm using it while my wife is sleeping, the spacebar in particular has a twang to it. Light has on/off button but I would've rather sen a dial that gives a brightness adjusaibility. Comes with 2 palm rests which sounds great but both only offer good support for the left hand, they should've provided one for gaming and one for workstation work.

Other Thoughts: All in all a good solid KB, great lighting features and solid build qualities, heavy so it doesn't move around on the desk

Pros: The keyboard is amazing, the colors are beautiful and the software is super easy to use. I use this keyboard daily, for gaming and just regular things. It takes a little bit to get used to, but its not a problem. Great performance, had it for about a month now and have no problems with it. Its great for gaming, i went from a razer deathstalker to this, and my performance game wise increased greatly. 10/10 would prefer it. The Romer-G switches are amazing, theyre not too loud, but give a satisfying click. And theyre great performance wise.

Cons: The only things that are bad are minor. The software can be a little glitchy, and the logitech phone app does get buggy sometimes. But no biggy. The keys of course are weird, but you get used to them. The palm rests provided arent the best, theyre plastic and kinda flimsy. But not that big of a deal. Minor things that can be looked past.

Other Thoughts: Great keyboard over all, just minor things that need improving. This keyboard has lots of potential.

Pros: I love the different color schemes. The keyboard just feels good.

Cons: I am still getting used to where the 'ESC' key is located at. It's in a little different location than my last keyboard I've had for years. This is really not Logitech's problem, just something I need to get used to.