Summary: The difference between membrane and mechanical is light and day. Never again will I have a cheap keyboard! The cherry red switches make for an effortless and enjoyable time both while typing and playing games. It didn't take very long at all to get used to this keyboard, and it seems typing has become easier than ever. As others have said, the wrist wrest is uncomfortable and has been solely dedicated to key cap storage.
Summary: This is hands down the best gaming keyboard I ever owned. Sure it's a gaming keyboard, anti-ghosting blahblahblah rollover. Yeah, it's got all that. What I wasn't expected was the workmanship on the keyboard itself, beautiful brushed steel and each key strikes with purpose. The exchangeable keys are easily removed and interchanged without any fear of permanently damaging your keyboard ripping keys out.
Summary: It's metal base is robust and keeps the keyboard in place, it will last for years. The keys are so responsive and fast, smooth yet almost clicky, Not mashy and mushy, but smooth with a slight firmness, or click. Nice textures for the special "gaming keys" Just wish it was wireless, but then again batteries are a pain to recharge.
Summary: The design is sturdy, the keys are nice and grippy. The hand wrest is in a great position and the keys are extremely fast and responsive. The ghosting of the keys basically doesn't exist, it updates your actions at roughly 1000 actions per second, great for FPS and RTS gaming. I cannot find a flaw with this keyboard, other than the keys are very loud (but its mechanical so I expected that when I purchased this).
Summary: I love this keyboard. Its solid and has fast typing action. Its also very durable, as sometimes I get excited and hit the keys quite hard. It withstands all of my abuse. The K65 version feels a little more comfortable, especially if you use the arrow keys heavily.
Summary: This keyboard is awesome. The USB3 port on the back is way more useful than you'll expect, the key action is wonderful (it keeps my roommates up at night just like I wanted), the replaceable keys are honestly quite cool but not bothersome enough to interfere with typing when you're not gaming, and the wristrest is not only awesome, but the function of storing the keys is wonderful.
Summary: I have done a ton of research on gaming keyboards for my boyfriend and this one looks superb! The reviews were all almost perfect other than some minor cosmetic details. But over a fantastic product for the price! Thanks Amazon!