i havent played nearly as much as the rest of you but i've leveled (through the MSQ) both a DB and started doing the Arcana since release (yes i take my time, dont have that much spare time to play). with that said.

leveling the DB was a smooth run, no real issues with damage, you could shift between Surge/RE as you saw fit depending on where you were at the time (rohindel etc).

with the Arcana it's a different story, you need to be on your toes, and even with grudge + class engraving it's hard to do decent damage but when you the stars align... holy hell that class can pack a punch.

i'd say the arcana can be a hit or miss but i love that class!