I have 2 of these type from True Temp. I got them at Target. They work surprisingly well. Most people complain that the probes don't last but I have had great success with this model. The probe wire is silcone and has stood up to lotsa heat and wet situations.
They also work great for cooking. You can stick it in the meat and close the over / grill and read the temps from outside.
I've got the silver $20 thermometer that target carries. I also have the cdn one that everyone likes and they both read the same temp. Another benefit to the target one is that I can leave the probe in the mash.