I used bluehost for several years, I always found them to be very professional and prompt in answering my questions. I also tried hostgator but I ended up not being that impressed and switch to bluehost which one of my friends had recommended to me.
I have never used fatcow before so I don't really have anything to say about them. But if i was going to do some web-hosting again I myself would use bluehost.
Edit: Blue host's service was always reliable and fast in addition, and their hosting panel is very nice to use.