I think the most crucial thing which makes people leave hosts is if they don't get good customer service. I left my old host not only because they never monitored the (probably crammed) shared server I was on, but also because when any problems arose, I'd wait days, sometimes weeks for them to reply to any tickets to sort something out.
The best thing about surpass is that every single problem I've ever encountered has been dealt with efficiently and at lightning speed by friendly human people whenever I've submitted a ticket. Sometimes it's so quick they've found and resolved the issue before I've finished writing a support ticket in thre first place. Ridiculously good!
