You asked what combo would do best in MY scenario.
In MY scenario I wouldn't play the new/current system. I would go back to the old system, where the C and PF pretty much camp in the lane, and dare the other team to beat you with jumpers, limiting that to a single shot, whenever possible. It also works in our advantage in that if you rebound well, you can get the fast break started fairly quickly for a guy like TP and RJ.
I think the personnel we have lends itself more to that 'old' system. In that context, I would take the better rebounder/scorer, which is McDyess.
Don't forget Antonio is actually used to playing quite a lot of minutes. If my memory serves me well, he averaged near 30 mpg the last couple of seasons.