I installed Windows XP on my MacBook Pro last night. The only real advantage I see from this is being able to take the Missouri Bar Exam on it. That is a pretty big advantage, especially with someone with penmanship like mine.
It seems to work pretty well, outside of the fact there's no real way to right click without adding an external mouse. I'll keep you posted if I find anything else unusual about it.
Oh, and my suspicions were confirmed. Using QuietMBP drained my battery almost 30 minutes faster than when I dealt with the irritating squeal. I really think they need to fix this, pronto.