I signed up Site5 on 21 September 2005 and said goodbye to them on 3 September. I'll have to pay $143.4 if I renew on anniversary, I can't find any good use of it yet so I decided to quit.
As a shared hosting they have done a good job for the last 3 years. There were problems from time to time but they have served me well in fixing issues and people are friendly.
Before Site5 I have also tried DreamHost and Yahoo if I ever want shared hosting again Site5 will be the one that I would return to.