So, yes and no.
Yes, from the standpoint of it will give you a better idea about programs you are considering or hadn't considered.
And no, from the standpoint of the programs don't care who comes by. Sure, they offer swag, and take down names, but if and when you become an academic attending, and you ask all of the other guys at the tables, they'll tell you it is essentially meaningless to them. They all do it because everyone else does it. Nobody ever talks about "that catch we got all because of the res fair!"
Hope I didn't burst every med student's bubble.