Pre-ordered two of these items and received them yesterday. Installed without any problems on both of our Windows 7 PCs.
My main concern was that the two devices would conflict with each other (as there is one for each PC in the house), but there was no such trouble - the software installed and picked up the controllers correctly.
Tested the controller with the following games:
Need for Speed Underground
Lego Star Wars: The Complete Trilogy
Batman: Arkham Asylum
All of the above games picked up the controller automatically and pre-configured the buttons without any trouble.
My only niggle is that I can't find a way to switch off the controller when I'm finished with it (except to leave it to time out after about 5 minutes). But it's no big issue at all.
I'd recommend this controller for anyone looking for a wireless PC controller for gaming - in my opinion, it can't be beaten!