I use rackforce. I havnt had a problem with mine, but then i dont have anything large scale on it. One thing about them that is good is they are on a borderline of two powergrids and backbones.(so i have heard)
Just stay away from Webserve.ca. They are HORRIBLE, horrible support, they mess things up, slow to resolve problems. and i heard they are a reseller. I tried them a while back when i just needed something quick and didnt do any searching. Bad bad bad.