Dumbells always trumps barbell in strength gains.
You must be a newbie. Many can bench 315 with barbells but can't do 150 dumbbell bench for a 1 rep.
Any experienced lifter will tell you dumbell strength is stronger then barbell strength.
fukk all this dumb shyt.
It depends on what you're doing. Wtf does someone curling 70+ pounds really mean.
Also practical strength trumps any type of weights period.
I don't give a fukk what someone can do with weights or dumbbells.
If you can't do double overhand, wide grip pull-up I have no respect for you.
If you can't squat twice your weight I have no respect for you.
If you can't deadlift 2.5 times your weight I have no respect for you.