In my experience it usually takes about 15-20 minutes to complete a PITT mission and that's with a full team of 4 players. So yes, the PITT missions are long compared to the Events but you get a lot of rewards when you finish one and especially if you get all of the optional objectives.
“Whoever fights monsters should see to it that in the process he does not become a monster. And if you gaze long enough into an abyss, the abyss will gaze back into you.”
