Ok, so I just want to share my experience with g400.
I'm a Quake player and as you guys know or maybe not... to aim well in this game you need as much perfect mouse as you can afford. Basically I've tried a lot of mice in my life, but in the end I finished up on a WMO 1.1a, Abyssus and g400. In my opinion as a hardcore gamer (think I can name myself like that, I play a lot of games), I think theese are the best mice you can get now, really. Some time ago I had to choose one of this mice (can't use 3 at one time unfortunately : P). It was a hard decision but I finished on g400. It's the best mouse for me. I was very satisfied with it's performance so far.
Unfortunately, the cable in my g400 broke. Burt I wasn't really distressed because I've been reading so much good stuff about logitech's warranty support. I just wrote an e-mail to Polish logitech support and basically they did rest. The DHL courier came to my doors two days later and picked my package with a mouse. They were informing me about everything and it ended up on a mail in wich they told me that they can replace my mouse with a new one mine version (older one) or the newest without prediction. They asked me wich one I want them to send me. Ofcourse I set I want the newest one. After two days I've got my new g400 without prediction.
just want to point that the logitech's support is unbelivable good...
If anyone is wondering about to buy g400 just do this. It's very good, flawless mouse. If shape suits you, there won't be any other problem.
p.s. sorry for my english, I'm still learning