Yeah,mig welding,,duty cycle is the thing,how much a weld you can put down with it in one pass,,nonrelavent,,,,if you want 80 to 100 percent duty cycle at 120-140 amps,,you gotta go big,,thats just how they make them. And thats what you want with a mig,,high duty cycles more than anything,with the amps you plan on running. Not saying you can't get buy with way less,,just take your time is all,,,,but duty cycle at amps you plan on running is the key to figureing out what machine you need,,not if it will weld 3/8 inch in one pass,,that one pass stuff is all bullcrap,,,what,,you reckon you can weld them amps overhead,,or uphill??? See,,it don't make any sense,,,just a gimick to try and relate to nonwelders,,,welders don't go into welding something that way,,,they run the amps they need for what postion and material they are welding,,and they make more than one pass if nessacary,,and it generally is unless you are welding sheet metal,,,don't limit your selfs,,,this one pass thing just limits you to what you can weld and in what postions,,,,thingy