Personally, in your shoes I would just run the W8 consumer preview until W8 launches. If you don't like it (and really cant just put up with it) then you can always buy Windows 7 afterwards.
I've been running it since the day the CP build was made public. Stability is maybe an 8/10 so far, where Windows 7 is a 9. Other than that, no major problems. I believe XDA-Devs have a program that disables Metro and restores the normal desktop. Might be wrong on this as I don't actually use it, just noticed a few users on XDA mention it.