Ricky, morning.... 2 - 8# butts would probably be max.... The reason I say that is, thermal mass of the meat will suck up all the btu's from the heating element... Total smoking/cooking time goes up with the more meat you add to the smoker... Increasing the temp of the smoker, does reduce the time needed but I think it takes away from the quality of the finished product... I smoke butts at 210 and 1 butt will take 15 hours or so in my MES 30.... Just the way I do it.... SmokinAl convinced me that 210 was a good temp to smoke butts at....
Dave