If you're doing RAF, quest with your team until level 15. Then just queue random dungeons. You'll get 2 - 3 levels for each dungeon...sometimes as many as 4 or 5 with all the dungeon quests. It's pretty insane. I got a 2-box of mages to level 60 in under 6 hours /played doing that (I'm leveling a few sets so I can power my Monk to level 80 on release day).