I honestly don't know enough about our prospects to argue on a per-prospect basis, but isn't the value of Bednar that he's only 24 and is under control for several years? Plus he's getting better each year (fWAR of 1.2, 1.5 and already 1.8 so far this season)?
Again, I don't know that you expend top assets for him, but Bednar seems to be more than a 7th inning rental