There's nothing wrong with temp guns but it's not an ideal setup. You'd have to move the substrate and check the spot that's over the UTH or heat tape just to make sure that the temps are correct. Another thing is you can't measure ambient temps or humidity with an ir temp gun. You'd literally have to check multiple times a day to make sure that nothing fluctuates. Instead, I can just peek in my terrarium and make sure that all my temps and humidity are correct.
I do see your point. But I use a ARS rack so little different then cage. Valid point. No disrespect mentv