That may depend on which Polder you're using. I have several models that I've been using for three+ years in both the big stickburners and in the WSMs that stay in the cookers for the whole cook. I use them both for continuously monitoring meat temp and cooker temp. I HAVE killed two Polder probes by kinking the leads in a stick-burner door, and I brought one to an early demise by positioning it such that meat was dripping into the joint between the wire and the probe. It definitely doesn't like that.
That being said, I have two ET-73s that I ordered way back on the first day that they were originally released, and I'm still using both of them. Also have a Nu-Temp with three probe units, which I usually reach for first. I see where there are now Thermopens with interchangable tips and available lead wires as well, such that you can hold the unit in one hand and reach way back into the cooker to check temps with the other. Andrew Delahunty at Thermoworks also told me that they now have two types of smoker probes that you can leave in the smoker while you cook, and the plug mount will rest outside so you can check the temp at your leisure. Not cheap, but fun toys!
Keri C
