I've got one of the Xbox 360 wireless adapters and it works nicely, however, there is one major fault with it -- Since it's wireless it has to be bound to each device you want to connect to each time you switch, so if you plan to take it back and forth between your PC and 360, its a minor annoyance. The bigger annoyance is that, to bind the controller to the new device, the controller needs to be turned on first; If the controller is currently bound to the Xbox, and the Xbox is within range of the wireless signal, you're going to turn on your Xbox without meaning to every time you want to bind it to the PC.

Any of the wired-veriety of Xbox 360 pads will work with your PC out-of-the-box though -- plug it in, Windows will download the drivers if it doesn't find them, and you're good to go. Its not as nice as wireless, but the way I figure it, I need 2 wireless controllers for the 360 for regular play and on the rare occasion that I have 3-4 people playing on one Xbox, I don't want to worry about whether or not I have enough batteries charged, so I went with wired for controllers #3 and #4. They can stay with the PC in the bedroom 99% of the time, and I grab them for the Xbox out in the living room when I need.

I do occasionally use the wireless adapter with my laptop when I'm on the road since I'd rather not deal with more wires than I already have to, and the binding issue doesn't come up, obviously -- also, battery life is better since the lappy is only powering the reciever, rather than a whole controller with rumble.