I have a Vision, Kamado style grill I have been experimenting with lately. I have 2 MES 40's and haven't been impressed with the temp control these units have. First of all, butts and shoulder in this area are $0.99 per pound. I prepared my Vision and got temp up to 250 and placed the rubbed 15 pound shoulder in a roasting pan I purchased lately. It has an inner rack that holds the meat off the bottom of the pan. I put apple juice in the bottom and did not use a deflector plate. The temp was allowed to wander up to 300 degrees. After 15 hours and a couple of hour resting period, the skin lifted right off leaving moist and very tender pork. I pulled it with my gloved hands.
I think butts/shoulders should be cooked at higher temps and not the 220-225 that I see on a lot of sites.