See title...which would you prefer in your pickup/farming group at lvl 45?

I got my dagger bird to 45 last night, love him, massive damage, not positive how beneficial the high damage is to groups.

My Paladin is 42, can easily get her to 45.

My Str Beartank is 43, can easily get him to 45.

I want to focus on one of them...so which of the three would *you* rather have in a random pickup/farming group? Which would be most useful to the success of the mission at hand?