I've heard a lot of good things about the RAT 5 and 7 and a lot of bad things. The mouse doesn't seem to be too good for FPS gaming but plays well for strategy games and the like. However, I've never used one for a longer period of time, though initial impressions wern't decent. At the end of the day it boils down to opinion and personal preferance, but if you're considering getting a new mouse I have a few to suggest;
Steelseries Ikari and Sensi
Roccat Kone and Kone+
Logitech G9x
I don't trust razer with mice after two deathadders breaking on me
Also keyboards! Again, at the end of the day, it's all down to preferance. However personally I look for what type of keys a keyboard uses over flashy lights and a gaming profile. For example mechanical keys I find give much more feedback and generaly feel better to me than domed keys. I.e. raised clacky keys vs low profile laptop type keys. I splashed out on a Steelseries 7G which has almost no media buttons or anything. Pretty standard layout besides the single key backspace and the left windows key being replaced by a "steelseries" key. This just allows you to use F1 through F6 in conjunction with the steelsieries key as media keys. So chuffed with it though and would reccomend it to anyone. When buying it it was between that and logitech's G19. Which looks like a beast!
A lot of these products are fairly pricey for what they are, although I think it is worth it. A more expensive mouse will last a lot longer and, in my opinion, feels nicer to use over a lesser mouse. For example I had two Razer Deathadders fail on me within a year or so. Since then I've had one Roccat Kone and although the rubber coating is wearing away, it works fine after two years use or so.
Also this looks fantastic!
http://www.amazon.co.uk/dp/B00606O9WS/r ... B00606O9WS
links;
Ikari:
http://steelseries.com/products/mice/st ... ri-optical
Sensi:
http://steelseries.com/products/mice/steelseries-sensei
G9x:
http://www.logitech.com/en-us/gaming/mi ... aser-mouse
7G:
http://steelseries.com/products/keyboar ... lseries-7g
G19:
http://www.logitech.com/en-us/gaming/mi ... for-gaming