I was always under the impression that the drivers on Metro Manila roads are pretty cutthroat and unforgiving, but now that I'm driving, I realized that that's not really true. Most drivers will actually let you pass/overtake (if you signal correctly so they know what you're planning), even in slow-moving traffic. The only ones who regularly won't give way are the jeepney drivers, but even so, I've yet to meet any with the extreme devil-may-care attitude I expected (knock on wood).
Also, I noticed that the roads are pretty effing scary on Saturdays. Twenty-wheeler trucks are all over the place, and I always seem to end up sandwiched (or worse, boxed) between them! Just my luck, my only real need to drive is on Saturdays, for the Nihongo class at UP, which is such a hassle to go to by public transport.
Meanwhile, I still don't know how to park and do U-turns. XDD