Good:
Currently I am with Joombyte and purchased their Dolphin200 package. I would have to say it has been nothing but a pleasure since I have moved over to them. My site is fast and response time for any issues is extremely quick.

Bad(Kinda):
I was previously with Cirtex and had some issue with alot of my mods after they decided to install suPhP on the server I was on. After several emails back and forth with them, they said they would not allow me to have the needed configurations in my .htaccess see more file for the mods to work. So I went somewhere else that would. This was back in my 6.1.4 (pre-D7). Not bashing them, just needed more permission they wouldn't allow.

Chris