Personally, I use singlehop.com

They have 24 hour phone, email, and chat support. I have literally called them at 3:30 in the morning.

You get a dedicated server - with or without a system admin.

You even have a dedicated account manager - so you have the same person to yell at if you want to.

I've been through some of the big boys (mentioned here) but I love this company.