Pros: Looks good.
Scissor switches feel decent.
Nice back-light with lots of colors.

Cons: Key conflicts
Won't allow my computer from sleep.
Seems to register random key presses when I'm not even touching it.

Other Thoughts: I really liked this keyboard when I first got it. It felt sturdy and the back-light and scissor switches worked just how I hoped they would.
Unfortunately however, as time has passed I've been encountering issues. The first one which I noticed, and the most major is that I have a key conflict between W and E. The keyboard will not register an E key-press while I'm holding down the W key. This is a huge issue on a keyboard which is advertised as being specifically for gaming. It means that in an FPS game any action which you map to the E key (i.e. mele) cannot be performed while walking forwards. (EDIT: I resolved this issue recently by turning the 2x function (which as another reviewer noted doesn't really work) on and back off. Not sure why it fixed the issue, but it did.)
Another issue which I have encountered is that for some reason the keyboard will not allow my PC to sleep. It will immediately wake the computer back up unless it is either unplugged or expressly not allowed to wake the computer in device manager.
Lastly, the keyboard will at random times decide to register a down arrow press and continue to do so (promptly sending me to the bottom of any web page or document) until I press the offending arrow key.

Maybe I got a lemon, but I have to say I would not recommend this keyboard.

Pros: Comfortable and responsive. The coloring effect is a nice touch and it's not too bright. Changing various colors is easy and speed settings is good. The back decently bulky even without the stands in use. Good for its price.

Cons: The enter key isn't too much of an annoyance vs the the \ key. I'm use to this key being near the numbers not right by the enter key. Other than that, good layout.

Died after a week. Keys would do strange things such as num pad "0" would mean "\m0", "E" would backspace, other keys stopped responding. Tested on my other machine and gave the same issues, the "M" would put my core duo into hibernate mode and there's NOT a hibernate key on this KB. Issued an RMA and waiting on newegg to return a replacement. Will change rating if KB does not give issues for a good 2+ months.

Got the RMA keyboard pretty quickly. Lasted for about 2 2/2 months until the Semicolon key stopped working. Tried everything and on numerous machines.

Time to get a new KB! Don't buy this one!

Reduced to1 egg because of this!

Other Thoughts: KB started to act normal the day I shipped out for RMA. The KB was acting up on a Friday evening, so I had to wait til Monday to ship out from our local UPS store. I didn't want to take the risk of it 'acting up again' as I've seen KB's do this as it's signs of a KB controller going out.

Hope it works out this time around!

Pros: the colors. the price. the LEDs.

Cons: space bar broke after 5 days. and the rest of the keys have slowly started going out.

Pros: Cycles several different colors, even pulsating between them.
Scissor-switch keys are quite quiet, and hold up to abuse quite well.
Feels very sturdy; does not feel like it might break if you hold it wrong

Cons: Double-speed key repeating function is... wonky. It just seems to cause input lag if you hold a key down too long. At least, for me anyway.
Can't tell sections of keyboard to be different colors, but is also not marked to be able to do so.

Other Thoughts: Bought this as I needed a decent non-membrane keyboard to go with a new computer build, so I didn't have to keep swapping one between computers, read the reviews, checked out Cougar's website page on it, and got sold on the lighting options and the keys. I love the scissor switches, they're super quiet unless you pound the keyboard. Had this for several months, it's been moved along with my little LANbox computer, and has started having issues, but considering the abuse it's been through, is probably the best keyboard for its value that I've ever purchased. Considering looking into a better Cougar keyboard because of the satisfaction with this one.

Pros: Very quiet, has nice blacklight colors with a breathing mode. The FN switch is easy to use with other keys that it controls, such as using F2 and F3 to change the volume.

Cons: A few annoying little things. The space key sometimes registers twice when typing, and some keys are more inclined to come off because of the scissor switches.

Other Thoughts: Some were mentioning the enter key being shaped oddly, but my old keyboard was like this so it didn't really bother me.

Pros: Work well
all what I need

Cons: none

Pros: Nice light colors, responsive keys

Cons: Key board at times has a mind of its own, the lights come on when pressing the shift key, randomly goes into game mode while typing, can not remove key tops for cleaning.

Other Thoughts: They need to include a program to turn off game mode permanently

Pros: weighty, comfortable to type on, illumination is useful in the dark

Cons: The keyboard doesnt draw enough power or something, when connected to PC (regardless of USB2 or 3 port) certain keys just continually press. For about a month after buying it (Dec 2014) it was great. around spring '15 the 'ctrl' key randomly started pressing at odd times. I'd find myself stuck in a loop of crouching/standing in some games, or when surfing web it would open new window/tab every time I click. Then after a few weeks it stopped. Now a couple months later it does the same, but with the delete key. every 5 - 10 wordss of this review I get a random few seconds of the delete button deleting characters faster then I type. It's really dissapointing

Other Thoughts: I recommend not buying this keyboard, as it's nothing but a constant string of headaches

Pros: Looks great. Sturdy. Great colors and function.

Cons: The Space bar- Unless you hit the space bar dead center, it won't register more times than not. Really annoying. Over all the keyboard feels a bit less responsive than it should, but if you're looking for a back lit Keyboard, this is decent for the price.

The enter key is vertical and not horizontal, not end of the world, just takes a little getting use to.

Other Thoughts: If not for the Spacebar, I would give this 4-5 eggs. Maybe it's just mine, so check other reviews and see if others make this complaint as well. Space bar works, but you better hit it dead on.
I have big hands to I tend to be a "lazy typer" and thus rely on being able to tap the edge of a key like Enter and Spacebar.

Pros: More responsive than any other dome keyboard I've used. The keys have tapered edges that line up really well to the adjacent keys but not too close so typing is fast and accurate. I don't have issues striking the wrong keys on accident while typing or gaming.

The LEDs are pretty solid and are switched using a single key that just scrolls through the options: off, orange, blue, green, violet, teal, yellow, cyan.

They keyboard has a pretty low profile and sits at the perfect angle for me so I never have an irritation in my hands or wrists during prolonged use.

Cons: Not so much a con but the enter key is vertical instead of horizontal. Kind of different from any keyboard I've ever used at home or work, but it's not bad. It just took me a couple days to get used to and I don't even notice the change now.

No matter which color you have the keyboard LEDs set to, the indicator lights for the caps, number, and scroll locks all light up as orange when in use. Was a little annoying at first, but I don't mind it anymore. Yeah, it clashed a little strongly because I always have it set to blue, but it's just another thing like the enter key that I got used to.

Both of these cons aren't large enough for me to dock it any eggs.

Other Thoughts: The keyboard really exceeded my expectations for the cost. It's slim, comfortable, and looks great. Over a month of use and it's accumulated zero dust or grime (no clue how, but that's always a plus) and the responsiveness of the keys feel exactly the same as when it came out of the box. I've got a feeling my thirty or so dollars will really go a long way with this keyboard.