What is that.....about 100 bucks cheaper than a new one?
looking at Amazon I'd say about that much, but there are a lot of bundles with a game and some amount of PSN + included for $299. these are not the new top loading versions though; I've been hearing people complain about the new versions getting dirty on the inside easier since the lens and everything is exposed when you open the top door. I don't own one myself so I cannot comment on the issue.
 here is a picture
of what I'm talking about:
the door slides back and forth manually.