Retail imo.
I mean, sure, that server will be fun for 2 hours...then you realize you've gotten everything in the game, and then it will become boring. I will admit, however, I do play on private servers every Tuesday morning from ??-12:00, if I don't have school that day.
But...if you need help connecting to one, or anything of the sort, I would be happy to help, just send me a message or something.