I had a long thread on the other forum about my GMG DB. I'll summarize it here. When I first got my DB which was probably something like 2012, I loved it. Perhaps I had beginners luck but just following general recipes yielded amazing results consistently. Ribs and pork butts were the main fare and it just worked. Sometime later I really started struggling with cooks with the primary issue being pork butts that were basically burning on the bottom and the rest developed bark harder than the worst beef jerky you've ever had. I started measuring grate temps with a Maverick and the smoker was consistently nearly 100 degrees too hot. Obviously I could adjust down somewhat but it was hard to compensate for 100 degrees. And it added up... the food coming off looked like it had all cooked at least part, if not all of the time at too high of a temperature.
I ended up deciding based on research that I should replace the controller. I ended up replacing the controller and temp sensor twice, once out of pocket and once on GMG's dime. It was still just ruining food more often than not. In a fit of frustration I finally gave the smoker away on the old forum to a local guy. Basically said if you're in Omaha and want a free DB come get it.
I almost gave up on the pellet smoking thing entirely but the bug wouldn't die. I ended up buying a Blaz'n Grillworks Grid Iron. Now all I can say is lest anyone think "this guy just doesn't know how to manage an imprecise device like a pellet smoker, its not an oven, you have to work at it" I will tell you that I'm batting 1000 on the Blaz'n. I measured the grate temperature at three spots when It was new and it was dead nuts on perfect. I've not bothered to re-measure as I've NEVER had a bad cook on it. Everything comes out perfect. I've never had a pork butt dry out or burn. Not even close.
Now the frustration is, a year after I bought my GMG my dad bought one. Fast forward to this past week over the 4th and he went to do two pork butts and ribs and guess what. They came out exactly like what I was having with mine before I dumped it. The pork butt was ridiculously dried out and borderline burned on the bottom and the ribs were impossible to cook low, it looked like they'd been cooked on a gas grill at too high of a temperature. I've not measured my dad's grate temperature but I recognize the "WAY too hot" symptoms that I saw with my own.
I know there are tons of people here who run GMGs. I'm not sure how you get along with them but I've had two of their smokers with a combined 4 controllers and temp sensors that just do not work as advertised. My Blaz'n is like an oven. It maintains temp to a T. It is ridiculous how accurate and tight a window it maintains. I just don't get how such horrible experience with the GMGs could be user error given my flawless results with another unit... very frustrating. I feel terrible that my dad followed my lead and bought the GMG given how his is now performing.