I perceive Bosh/Lee as quite a bit better than JJ/Amare - these last couple playoffs have me convinced that he's not an integral part of a championship team. I also perceive Bosh as having one of the best ten seasons in the league this year....I don't really feel the same way about Amare.
So individual player perception is part of the issue - if you think they could be a 50 win team with Lee/Bosh, then adding Davis doesn't do harm - I guess what I'm saying is that with Lee/Bosh, I could see them going 50-32 in the East whereas Amare/JJ gets you around .500. If you're winning 50 games already and are getting to the 2nd round without the guy....I'm not as down on overpaying for a FA. I would be down on adding Davis with just Amare/JJ; that takes you from .500 to like 47-35 or whatever.
Figured I should clarify that I percieve a big difference between Bosh/lee vs Amare/JJ (whether I am right or wrong is a seperate issue).