Just gave the Alchemy viewer a little test run. Saw maybe a 10% increase in frame rate while running about half the size of my regular FS window. 
It also reminded me how much I hate the CHUI changes that LL pushed a while back.
Yeah, I'm not seeing any real performance improvements. But I love moving around using my Xbox controller :3
If it doesn't interface with the Powerglove I can't really be bothered. 
In all seriousness, Xbox controller support on OSX is really bad on a good day, otherwise I'd try it out.
Xbox controller works wonderfully on Windows... but that's to be expected. :3
Yeah, I actually have an old windows laptop set up for retro gaming. My Xbox controllers work fantastically with it.