UltraspeedUSA is located at VDI. As in there servers are at VDI. There support is pretty good. They ran into some problems last year, but have pulled out of them pretty well!
The Php Support Desk
Custom programming - kunal @ e-phoria.com
http://www.pingzine.com - Ping!Zine. the FREE, FRESH and EXCITING Web Hosting Magazine...
I just got my server running with VDI, and I must say, I am impressed. The support has been great. I had a few questions about how some of the things on the server worked and sent in a support request. They emailed the answer in less than an hour, and called me the next day to make sure everything was working correctly. They have even called me to check on how things are going when I haven't sent in a support request.