Which is better barbell front raise or dumbbell front raise?
Depends on what you are trying to accomplish. Barbell Raise incorporates both sets of muscle groups at the same time, I would think that this coordinated muscle movement would make that muscle group stronger.
Dumbells isolate muscle groups, which makes each side work by itself. This strengthens each side independently.
I see no downside to either. If you are using this as part of your shoulder workout, the alternate days you use the lift. Bar one day, the next time Dumbells.