I just got one of these remote sensing thermometers. It reads the cooker temp as well as the internal meat temp.
It is very accurate, I checked it with boiling water and it came up at 212 for the internal and 213 for the oven.
You can set the cooker and take a nap and it will beep of the fire goes down below what ever temp you set, or if it goes higher than you set. It also will alarm when the temp of the meat reaches its temperature, AND you can take the remote receiver all the way inside where you want to be and you can watch the temps.
I do have one complaint. To set the temp limits below the unit's preset value, you have to step around the whole range of temperatures one degree at a time, and then quickly store it in memory, or you have to do the same thing all over again. I find this to be an nuisance. It should have a step down and a step up control, but it doesn't.