Hey KorgTurner,
Maybe I can help you out with this one. Exactly the same situation as you described (family nearby, saving $$$, know I'm a good match for the dental school, etc) except substitue Buffalo for Philly. I spent my summer before dental school in Boston and am also INFATUATED with the city.
I was so sad to leave because I was commited to be in Buffalo for the next four years for dental school and there was no way I could be in Boston again till post-grad. Buffalo is an absolute gray town for me who, like yourself, would much rather be in Boston or Philly. There aren't enough words to explain how much I dislike Buffalo (Buffalo the city, not the dental school. I love the dental school).
But it's actually worked out pretty well. My family (mom, dad, bro) lives in Buffalo, and they have been extremely helpful to have nearby in dental school. Food and laundry, enough said. Actually, one time during second year I was so swamped, my parents came to my apartment and made me dinner. And I've met lots of cool friends in dental school and love the dental school experience I'm having. Not to mention all the $$$ I'm saving by attending my state school rather than the privates in Boston. So except for the drab, cold, dying city of Buffalo, everything else about attending dental school here has been great. And I think in your case, since you actually like Philly and Temple, you should save your money and go to Temple. That $$$ will come in handy when you try to buy a practice after dental school. It's not worth it to blow it just because you want to live in Boston when you've obviously realized Temple will give you as good an education and you will be happy at Temple.
Here's what I say to myself when I get those "I miss Boston" moments. "I'm definitely applying to residencies out there. And when I get in to one of those, they're going to be paying me to do my training and live in Boston!" You can always do your GPR/AEGD there. Or work there since Pennsylvania and Massachusetts are both NERB states. When you pass the NERB exam in Philly, you can work in any of the 15 NERB states, and Mass. is one of them.
If it makes you feel better, here's what I know about "why BU sucks." Although they have the $1500/year DVD curriculum, I believe it is still optional there and you can purchase textbooks from the school instead. But, more importantly, Medicaid in Massachusetts SUCKS. Their governor basically got rid of almost all dental coverage last year. It has been a big problem for the Boston dental schools since many of their patients were Medicaid. BU did implement some community programs to counteract the patients they lost when this change occurred.. But if Temple has patients knocking on the door and a waitlist to get into the school, the clinical experience will probably be better there.
Good luck with your decision! Boston is awesome, but save it for when you'll get paid for being there. Go with your gut reaction for Philly/Temple for this one.