I set mine with coherence, therefore both OSes are on the same screen, i dont even notice the switchings, everything is pretty smooth. As a matter of fact, firefox on windows 7 is the fastest for browsing. I really dig it.
Other then the 79.00 I think I'm going to give it a try. I was lucky enough to just get a 21.5" iMac intel quad core i7 w/ 16gb ram so I think it should run well.