Rowan, without a doubt.
PCOM is an excellent osteopathic medical school, there's no doubt about that. But Rowan is an entirely different animal. It's a state school, with resources that put some MD schools to shame. It has REAL research - some of the most exciting breakthroughs in Parkinson's and Alzheimer's research are happening there now. It's affiliated with a REAL, major university, and that's actually important. It has its own teaching hospital ON SITE. Its rotations and clinical education are excellent. It has its own residencies, in competitive fields!
Also, as a DO student I hate saying this, but it can be important: In the area, Rowan has a MUCH stronger reputation than PCOM.
PCOM has some of these things, but Rowan beats PCOM in virtually every category. Rowan vs. MSU or TCOM would be a real matchup.
The only way this choice could be more obvious would be if you were an NJ resident eligible for in-state tuition! Oh wait...