PA for the completion of end of raid/dungeon quest

[Jalliah]

I find it hard to believe onslaughts can compete with the 4-5 PA/hour of grinding mobs, of which there are more than one spot.

They can't. But they do give other things, like planarite that's been mentioned, rep if you're after that and puresources which provide needed mats for raid consumables etc. So if you're just after xp, grind spots are more efficient but if you need xp plus the other things they are much more efficient use of game time.

[Ladara]

I find it hard to believe onslaughts can compete with the 4-5 PA/hour of grinding mobs, of which there are more than one spot.

I would have previously agreed with you but most of the areas you can grind mobs (at least on the server I've been on) have been discovered and are overrun. With Onslaughts you can (and should) go from place to place farming mobs from invasions getting a nice amount of planarite and XP. Also for everyone not fortunate enough to be a cleric if gives them easier kills with canon assist and anti planar augmentation.