I'd want to be Team B. The upgrade at QB is nice and you're not giving away a lot to get it. In order for this trade to be worth it for A, he has to be *really* shallow at the RB spot. Berrian and Ocho are both speculation picks this year, but the ceiling's a lot higher for Ocho than it is for Bernard.
Basically, player A is downgrading at 2 positions to pick up an aging RB on a crummy team with a gawd-awful O line. It's possible that move's an improvement to his overall roster (making this an acceptable trade for him anyways). But it's doubtful. And if he did need an RB that bad, he should downgrade a bit further at the QB spot and try to pick up a strong play rather than a situational at best injury prone disaster.