We have pretty good luck with them. OTOH, they also provide our colo service and we just light the fiber between there and our office.

We've had some run ins with their service (it's not our stuff, it's your equipment! No it isn't, I've replaced every single component that I can, aside from your freakin' fiber...)

My coworker and I figure we're actually being limited on our D/L speeds by our ethernet in office (10/100) rather than our internet connection.
I am the Doctor, and THIS... is my SPOON!