I've tried using electric pumps, but they never seem to hold up. I've had my old six shooter manual pump for over 30 years and it still works fine. I've had electric pumps now and then when I buy guys out of the hobby, but they never seem to hold up. For my gas planes I use a geared manual pump which will fill a 16 oz. tank in about 38 turns. If I was flying a 40% 150 cc plane with holding 48oz. tank I would probably get a electric. I think the geared pumps work pretty good.