Mine arrived today, installed and working without any problems. Very pleased with the upgrade from a Logitech Cordless Rumblepad 2. Again, all keys mapped and flagged in GFW games and the rumble is back in many of them too. It was disabled on the Logitech for most games.
Prince of Persia is much more fun now that the on-screen cues are only 1 color button and a short abbreviation. Plan on going back and trying some other games that I played through with either KB+mouse or the Logitech, like Assassin's Creed, GTA4, maybe even Gears of War! Thanks again OP, I would've never justified spending $50 on this with a perfectly functional Logitech, but at $25 shipped I'm extremely pleased.