I've been hosting my own content on the web since, oh, 1995. I've been on many hosts over that time, moving sites from host to host. During that time, I've been on some good hosts and some really awful hosts, and I have really yet to find the ultimate host that I can recommend unreservedly.
Perhaps you have been having sites hosted long enough to have acquired some horror stories. A while back, I had my sites hosted with a company called A World Wide Mall. AWWM was pretty reasonably priced, but as with most hosts, the customer service was pretty lousy. And one day, the guy who ran the service decided to fold up the company and move on without notifying any customers. He just took his datacenter and left. With all of my data. Lovely.
I'm sure that folks have similar (or worse) stories. I have had service where I thought I was getting protected backup and redundant storage, when really it was all on one box and when the box died, I lost a lot. I tried hosting at 1&1 once, and after playing with it, I immediately filled out their cancellation form. Total time with their service: about 5 minutes....
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