Well, I have to say that if you're using a Zoo Med thermometer and it's either a strip type, round gauge or a digital without a probe end, you're not getting good readings because those can be off as much as 20 degrees when compared to either a temperature gun or a digital with a probe. So, unfortunately, you're not going to be able to get an exact reading from it. I think you must realize how important good temps are with their overall health.
There are a lot of products on the market that either don't work or are dangerous. Unfortunately, most pet stores are only in it for the money and none of us here make anything with all the information and advice we give, just the satisfaction of helping owners & their beardies and having the owners make the necessary changes so their beardie can become and stay healthy. We do it for the love of beardies.
If you'd rather listen to the pet store owners, that is certainly your choice. The members here have an obsession with beardies and that is what has brought us all here. Have you ever met a pet store employee that had an obsession with just beardies and has had as many yrs experience as most of us here have? A lot of us have raised our beardies from very tiny babies (myself included) and there isn't hardly anything that we haven't experienced, not to mention the many hrs that we have spent helping and advising owners with all sorts of minor and serious problems. The choices you make are totally up to you. If you decide you need/want more help, we are here. Otherwise, we hope your beardies can be healthy and live a long life.