Trust me, you can do far worse than Vidro. Personally, I would pay a fairly decent amount for him in any league.
Isn't Walker platooning? I'd rather have Vidro by quite a bit.
Dropping him outright would be awful. You can at least trade him for something. Personally, I've never liked running platoons or riding hot hands, because I like to know what sort of production I'll be recieving. I'm the more conservative type, I assume, but if you're cool with using Marlon/Todd/etc. it could be worth a shot. I'd give it a while longer before calling it quits on Vidro...this is coming from a dude who owns RAY DURHAM at 2B...trust me, you can do worse.