My only concern with these three in MIA:
Chemistry.
Who would be Alpha Dog - Wade or Lebron? Assuming both Lebron and Bosh goes to MIA, then I think Wade would want to automatically default to Alpha - and could Lebron deal with that?
Would Bosh deal with less shots? He was Alpha Dog in TOR, but he'd certainly get less opportunities in MIA. We know that JO would still expect a decent amount of shots.
Another thing? No great PG. Wade and Lebron are great passers, but I'm talking about a pure PG. Chalmers is decent, but could he keep the team happy?
The last time a Great Three was Assembled? Summer of 2007, in Boston. Each had to defer to one another to make it work. It worked out (and continues to work out) well for us. Even with that, I think Ray had to give up the most.
Now, who out of Bosh-Wade-Lebron would be willing to give up the rock?
These three (Lebron, Wade, Bosh) are still rather young - would they be willing to not win for a few seasons? Our Big Three wasn't assembled until each was in their 30's.
Sacrifices would have to be made, that's all I'm saying. When's the last time a team had three players in the top 20-25 scoring? Even with out Big Three, we've rarely seen the three of them top 20 pts at the same time.