It worked great. I screwed up and didn't get the lid seated well, so I overshot the 250 target. I made a quick trip home to see why it was running hot, fixed that, set it at 275, and it was holding 275 by the time I got back to the office. Before leaving the office for a 4:00PM appointment, I used my phone to set the temp at 250, and it had that dialed in and steady before my meeting was over. As I left the meeting on the way to the grocery store, I set it at 225, and it was holding 225 by the time I finished at the store. From the store, I set it to 200, and it got down to there while I was unloading groceries at home. I decided to use it to do a reverse sear on some burgers for dinner, so dialed it back up to 225. It climbed back to 225 and held that for around 35 minutes until the burgers were ready for searing on the kettle. After that, I closed the top vent to around 1/4 open and set it at 160F (I've read that 160 is a decent holding temperature for brisket). It took around an hour to get down to 160, but it got there and held it. I've read that you can cold smoke salmon at around 110F, so after it held 160 for awhile, I closed the top vent completely and set it at 110. It's been around 1.5 hours, and it's down to 117. I'll probably let it burn through the night to see if it can hit and hold 110. I suspect that it could probably hold 110 if I started with a thin snake set-up. I doubt I'll try that any time soon. The port forwarding worked fine for when I was away from home, and all I had to do was uncheck one box in the router software to turn off port forwarding when I got home.
I'm loving this thing. Set-up was a pain, but it was well worth it. This feels about like setting the oven temp and walking away ... except that I can't monitor and change settings on my oven from my phone while I'm at work or running errands, and ovens don't hold temperatures anywhere near this steady. I bought a brisket at lunch for another practice run this weekend. I'm looking forward to dialing in 275F before I go to bed and sleeping well, knowing that it'll be at 275 when I wake up.