Not always MiRai. When I was levelling my 2nd team of shamans, By joining the LFG tool, I would get double the end completion bonus for some reason. I think it was a bug. Simply put, that xp bonus you get for completing a random dungeon, that tripled due to RaF and i got it twice. At lower lvls this was INSANE xp and I went up a huge amount of levels for a 10 minute stocks run.

So for a very small niche, boosting wasnt the fastest haha.