Petro VS the Draft

As a question topic today I bring up the relative happiness with Johan Petro and his improving game contrasted with the apperent lack of enthusiasm for this year's draft class. My question about Petro, as well as Robert Swift is this: WHAT IS THE LOWEST DRAFT PICK YOU WOULD TRADE EITHER OF THESE PLAYERS FOR?

I'm saying I'd have a tough time taking the #4 overall pick for either Johan or Robert. They are big and there simply isn't a lot of that available.