The "For windows" version is simply bundled with the wireless receiver. Once you have one of those, you can use any 360 controller.
I regularly use both the controller that came with my 360, and another 360 controller that I brought separately (with no "for windows" marking) in addition the controller that came with the wireless receiver.
I regularly use both the controller that came with my 360, and another 360 controller that I brought separately (with no "for windows" marking) in addition the controller that came with the wireless receiver.
I assure you that all 3 are identical.