Hands down my favorite instant-read thermometer. It's not quite as fast as the Thermapen, but for a quarter the price it doesn't have to be. I own 8 of these for a reason.
Why buy a Thermapen if the Thermopop is so good? Well, because it is still the baddest thermo on the planet. If you're paying the penalty for one, then get the IR version!
This is probably the best-kept secret in competition bbq. Every team I know has several. They are reasonably priced, accurate, no frills but everything you need in a temp monitoring device.
If you want a unit that has it all the Signals is it. Lots of probes, wifi, Bluetooth and cloud storage. If you don't need as many probes and want to save some cash, check out the Smoke.