I haven't had experience with the other two, but with EV1 I have, and I'd recommend staying far far away from them. Here's why:
Typically, ev1 will shut your server down if they even get a hint of an abuse complaint, or DMCA complaint. If your server is shut down, it's DOWN for at least a day while their "investigations" department can "investigate" it (usually coming up with nothing at all).
Secondly, if you have any problems in bootup, you can forget quick responses, or being able to actually GET someone on the phone directly to help you. Open up a ticket, they'll forward it to "investigations", and it sits there for hours on end.
EV1 is the worst in the "trained monkey" and "canned responses" department, and I'm not kidding here. They don't read trouble tickets, they simply enter in some canned response and it's usually WAY off base.
Unfortunately, EV1 is one of the largest out there, and they could care less about small time customers, or providing realistic, real support.
You may also want to check out fastservers.net . Their prices are a bit higher than most (not by that much), but their support and networks are definitely worth it 100%
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