Hey JMB, I love mine! I have a full sized one and a mini that I take camping with me:(
https://www.smokingmeatforums.com/threads/my-uds-builds.277660/ )
What I love most (besides the cooked final product!) is the whole diy aspect of them, building them from scratch, and the look on new people's faces when they eat some wicked meat that came out of an old scrap drum!
What I do tell people who are interested in them though, is that it does take some practice and playing to run them. I'm pretty confident in my full sized drum now, that I can get it loaded, lit, and adjusted right, I can go do other things and trust it will stay consistent. It took a bit of practice to get there. I've built 2 other uds' for 2 different friends, that are both having trouble getting them to run smoothly. They've both only tried a couple of times each though, and I believe their main problem is not being patient enough. When you make a small adjustment on the air inlet, it takes a while to change, neither can wait for it, and start messing more and more with the adjustment. Then they end up chasing the temps up and down. I get about 100 texts from them every time they fire them up. I've read where someone compared it to steering a ship, and that's a very accurate statement.
I built an offset smoker this summer, and my plan was for it to replace my bigger drum, but, I'm not sure I will get rid of it now, I love that thing!