I've been through MNL 29 times - mostly T2 on PAL (but also T1 on Qantas and T3). While the facilities and services are poor, I have never really had a major inconvenience with things like immigration being swift and speedy. I kind of liken to grocery shopping - I love a full service supermarket, but if I need to go discount I will do it.
About to make another trip in September - I might change my mind then.
The airport reflects the sad state of tourism infrastructure (poor bus and ferry terminals etc).