I have used it (once to Cebu on Cebu Pacific, once back from Palawan on the same airline) twice in the past two weeks.
Dropoff is easy: taxis stop right outside the door.
Checkin was spacious. I had about a 15 minute wait: there was one line for all domestic flights, and about 12 staff at the counters. It was similar for international flights.
There are three, inadequate, kiosks upstairs before you go through to departures. There is a tiny Jolibee, a tiny Mister Donut and another stall. Jolibee has a few high tables at which you can stand: there is some general seating, but not enough.
Permanent shops are not open due I suspect to matters regarding final payment not having been resolved (typical of the Phils).
I did not find aircon. too cold but then I come from Melbourne, the more temperate part of Australia.
Once airside, guests are prohibited (even for domestic flights). There are about three food stalls: GoNuts (doughnut stall) and two others, including a sit down cafe (perhaps 20 seats).
There is plenty of seating while waiting at the gate lounges, and there are some monitors showing flight departures (not many, but they are bright and colourful).
Aerobridges are now in use for those sitting in the first 15 or so rows of (say) an A320: like in Australia at Melbourne or Sydney, those sitting at the rear can walk across the tarmac.
The airport shows other signs of incompleteness: there are some vacant spaces, but nonetheless it is a huge improvement on Manila's old ramshackle Domestic Airport.
Coming back from Palawan, my luggage took 30 minutes to arrive. The belts work well.
Instead of getting an airport taxi (yellow: P70 flagfall and efficient) or the older ripoff airport taxis (fixed rate), I walked across to the street and caught a 'normal' taxi as I was going 60 kilometres.
However the yellow and red airport taxis are fantastic: drivers are reliable, and uniformed.
Anyone with preconceived notions about the Phils. should note that Terminal 3 is a pleasant introduction, particularly if you enter Phils. via Cebu and then travel on a domestic flight to T3 at Manila.
By the way, Cebu Pacific's timekeeping was (as I have found previously) better than Australia's QANTAS (not that this would be hard hahaha LOL). Cebu Pacific's A319s and A320s are only two to three years old and the airline (despite some criticism from Filipinos) seems pretty reliable though I am sure its punctuality is imperfect.