Im using 2x 4.5w motors on 3 beasts and a prodigy and have no power..heating..exhausted problems at all...no side wobble issues at all...along with my v3s...all 3 models are more than adequate for what I do...I use standard needles and disposables no cartridges at all...and rarely go above a 15mag...after a full 10 hour day...they cool as they were when I started....keep the ink from dryin on the needles..keep well maintained and lubed correctly...not to much tension on tje needle retainer...these motors gunna last years...not tried.the 10w I must add...and like said...the stigma team just wouldnt release something that was pointless or unusuable so it obv has a place and purpose...and again like it been said...if ya pushing a 45 mag cartridge....thats alot of resistance so the extra juice would obv be benefial to the motor life....suppose ya wouldnt use a sledge hammer to hang a picture nail