Couple weeks ago I bought one of those Afterglow controllers (the ones with the blinky light in the box) at Wally World so that my room mate would stop crying about how he can't play Borderlands on PS3 with the Six Axis controllers. I decided to plug it into the PC and see what happens and it worked with FFXI right away. It picked up the same control inputs I have for my Logitech.
I would not recommend this controller though for a few reasons. The buttons are very small and close together. The whole controller is oddly shaped and small, it kind of reminds me of the controllers for the Gamecube. The lights and rumble don't work (I haven't tried and special configurations to make them work) unless you have the lights on constant mode.
I'll keep it around in case I have a controller blowout (Logitech... bound to happen) but not going to use it otherwise. Just thought I'd post in case anyone else was looking at these and wondering if they would be PC compatible since the box does not indicate that it is at all. They come in 3 colors too, green, red, and blue lights.