Hey Skif, if you're going to spend a decent sum on gaming headphones, I honestly recommend something from either SteelSeries or Razer.
Linkage to SteelSeries headsets:
Audio - SteelSeries
Linkage to Razer audio:
Razer | For Gamers. By Gamers.™ | Gaming Audio
If it's possible, I would try and find some of the models locally so you can actually touch and even try on the headphones before purchasing them.
The Creative HS-1200 look ideal on the surface, but I think Creative jacks up the price of any "X-fi enabled" product, and no one is really sure if it works. A lot of the audiophiles I have spoken with said it's complete marketing garbage that Creative uses to help propel average equipment and make it seem more relevant. I've seen a lot of the Creative stuff first hand and can't say I noticed much of a sound difference between the stuff that is x-fi compatible and didn't use x-fi.
Soundwise, it's hard to try and figure out which headset sounds the same, you know? Some people swear by Bose audio stuff, while others say it's overpriced garbage. I won't say it's garbage, but it does seem overpriced when compared to other similar products... gaming gear is the same way.
But if you are looking for wireless, then I guess the Creative headset will be the ideal one you're after. But like I said, I think that x-fi garbage adds an additional $20+ to the price tag. If you're okay with it, then go for it!
As to gaming mice being cordless... my friend, don't hold your breath. The companies making gaming mice want to have speed between the mouse and actual movement in the game as fast as possible, and it seems like a cabled mouse is necessary for that.
I'll have to go out on the hunt later tonight to try and find something suitable for you.
