I have a 2008 Fuel 8, I like it, I bought it because it had pretty decent components that are quality, and I wanted a bike that was, not a downhill ridiculous mountain bike, but still, something that felt more capable on the trails I do than the Specialized XC rockhopper I had before did.
My mindset was, if I'm going to spend 1300 on some new bike that really isn't much of a step higher than my lame XC bike, why not spend 1000 more and make the investment 10x more worth it by getting an exponentially better bike?
The only thing with the Fuel 8 for me is its handlebar, it is a little too XC oriented but it's no big deal to me for now.
I can't speak for the other bikes, I think I skipped over the Santa Cruz because it was too expensive or I didn't like the components, I forget.