As a second year MD student in the Philippines (I am a US citizen of a non-filipino background), I can recommend the following:
1) If you have a shot at a US medical school, attend in the US. Your USMLE scores will be better, and combined with a domestic MD degree you'll have an easier time matching. Also, most US grads start residency right after graduation. Most graduates of MD programs in the Philippines end up in residency a year or two after graduation. The reason for this is that US med schools allow for USMLE taking during the school year, schedulewise. They also groom you for the exam. In the Philippines, you do it on your own, and most have to do it after graduation and miss the matching program deadlines. The year or two of unemployment after med school hurts more than a dead year before admission.
2) If you won't be accepted in the US, the Philippines is a good option. I strongly recommend considering schools not only in Manila but outside. Less foreign fees, and calmer environment give schools outside the capital an advantage, IMHO.
3) Don't go for the "best" MD school in the Philippines. They will load you up with so much extra work, you won't have time to study for the MLEs. Go for the midrange ranked schools instead. You'll get same books, same instruction.
4) Unless you have a very strong background in pre-medicines (a BS in medical technology for instance), i don't recommend enrolling in a PBL program. In general, Filipino style learning is do-it-yourself. Even in traditional settings, students don't ask a professor a question unless they've looked in the book and failed to find an answer, and then asked a top student in the class and she/he did not know either. If you go to PBL route, you'll be COMPLETELY on your own. And without a strong background, medicine in a self-study setting will be hard to swallow.
5) Philippines is not a rich country. Living here requires a bit of a light perspective on things. If you like impeccable services, always getting what you pay for, and are bothered by stray dogs or weird insects - you'll have a hard time adjusting. If you are the rugged type who doesnt care much for luxury and glitter, you'll find the Philippines far more functional on every level as compared to, say, Mexico.
6) Many disagree with me, but I think the Philippines is an infinitely better option compared to the Carribean. There are many reasons for this and I won't enumerate them now. And while I still question myself if I made the right choice by going to the Philippines instead of repeating my premed and applying in the US (My MCAT score was good, but my undergrad and premed average was low), I am really glad I didn't fall into the Carribean/UAG money trap! These are good schools, but the 10x tuition amount doesn't give you anything that Philippines won't give you. Plus some things are lacking in the Carribean as compared to the Philippines.
To sum up: If you can attend in USA, do it. Even if it costs a year or two. You'll be happy you did. But if going abroad is a must, come to Philippines, its a better choice than many others.