I tried it. I like it, overall. After an arduous installation, it takes forever to boot the first time afterwards. On subsequent startups, I don't even notice a difference in loading times. It even says "Windows Vista" on the splash screen instead of "Windows XP", a nice touch. I get the thumbnail preview of Vista, but to my knowledge not Aero, so it's Vista Basic/WinXP kinda thing I got going.
I give it a B+, overall. It's better than what I did and it's "Smoother", too.