Well, you can't really travel throughout the Philippines with public transportation because, ... it is an archipelago but just around regions and stuff, I'd say it would be terrible. Public transportation in the Philippines isn't pleasant, I tell you.
Public transport consists of tricycles, jeepneys, and buses (ones with air conditioning and ones without).
Tricycles, jeepneys, and buses without air-conditioning aren't very clean. Besides, they're "open" and you have to breath all the polluted air. That aside, the seats could be ripped or broken and being that most roads are messed up and bumpy, you'll be banging your *ss half the time. Being in a jeepney, which usually, during certain times of the day, can get really packed, is like sardines in a sardine can. You just get squished in there with all other people. The fact that Philippine weather is also hot and humid and people are sweating all the time isn't that great either.
Air conditioned buses are much better but buses don't really go into the 'little streets' and corners and more interesting places. Tricycles are more private but still, not too good.