I've used it twice so far. Once for a pork shoulder, once for a brisket. For the pork shoulder, everything worked pretty well. Took a bit ot get to temp, but after that was good. 

I had a lot of trouble getting to temp this second one. I even set the grill to 250 and it wouldn't pass 215. It was 50 today, so I know that could impact it, but I feel I shouldn't have to buy an accessory in the insulation pad to get it to work when it isn't super cold. 

I'll be cleaning it and testing it again this week to see where it's at.