Some good points.

Don't get me wrong, I'm definately not saying don't do it. I think for alot of people there would be a balance between using both.

As to what the difference between the two... Dumbells put alot more strain on your chest and stabilizing bench muscles because now you not only have to push up but you have to deal with keeping the DBs are the correct distance apart etc. This is where alot of the differences in strength comes about I would say.

With a barbell you only need to really focus on moving the BB straight up and keep it from moving front to back.

IronWorker