I was with pair, and rather pleased with their speed for a while. Somehow I've got the feeling they've started cramping more users on their servers lately (adding larger harddisks, and load averages have gone up significantly on 3 different accounts/servers) but it could be me. One large UBB was closed down because of system overuse lately, and a CGI reaper was installed.
Anyway, I decided to stay ahead of trouble and as boys need toys I ordered myself a nice little dedicated RaQ3i at DigitalNation. Very pleased so far!