Philly is 240 individuals Maverik is 160 JR is 240 (120 direct/120 through 3dbc)
I think all three are reasonably sized, elite top of the line showcases.
3dbc has 600 players (of which the top 120 go to JR) -that is top 120 as determined by 3d -3dbc is not in and of itself a recruiting showcase it is a 3d run tryout for a recuiting showcase