Mine was about 15-20 seconds for a charge. I also question the accuracy of them. They probably aren't that much better than plus or minus .15 grains you already have if at all. Where the electric dispenser shine is for a lot of people is shooting big stick powder in rifle cartridges.
In my opinion a .3 grain spread from a mechanical powder measure and flake powder is pretty good. I'm happy with that myself. If that isn't good enough, then there is nothing that can beat a mechanical scale and trickling it yourself.