Both are great schools with a long history behind them.
(assumption based on your screen name)
PCOM is the largest civilian supplier of military doctors nationwide. Among its alumni is Lt. General (Ret.) Ronald R. Blanck, former Surgeon General of the Army and the current President of TCOM/UNTHSC.
There are frequent guest visits by military docs who give lectures and advice to HSPS students. Check out the website at
http://www.pcom.edu/uniformedservices/index.html
PCOM is in Philly ... and with it you get the typical Mid-Atlantic weather pattern ... and traffic pattern. There are plenty of stuff to do during your down time in the city. And if you want, NYC is only a 2 hr drive, Atlantic City is 1 hr drive, Washington DC is 3 hr, and Boston is 4-6 hrs (depending on traffic, how fast you drive, etc)
During your first two years, you can interact with other medical students from Philly's other medical schools either through clubs or sports activity. The school regularly bring in guest lecturers who are professors at our neighboring medical schools.
Most of your core rotations will be done in Pennsylvania or New Jersey with some sites in Delaware. During your MS-III years, you will interact with many medical students on rotation from Philly's other medical schools. Because of location and history, lots of PCOM alumni can be found in residency at Temple, Jefferson, Penn, Christiana, Penn State, Drexel, etc.
Good luck with your choices. Both are good schools and both will educate you and turn you into a good doctor.