Saves money and prevents "tape arms". After working with those heavy tape dispensers for a few hours my employees always used to complain.
We had a manual dispenser and switched to the electronic one. The increase in speed was amazing. We used 4 sizes of master carton, so it was very easy to know what size piece of tape to use. The electronic machine easily doubled the rate of taping master cartons. Your pre-stuck boxes sound interesting, but don't you end up with a huge pile of trash (the backing) after a day?