I have both and they always fall within a couple of degrees of eachother. I now have 2 on-boards, 1 R.S. temp gun and one Craftsmen temp gun. All of them are within a couple degrees. I like the Craftsmen gun since it has a Red Dot so you are certain what you are temping, AND, it has a Max Temp button, that when on, will keep taking temp and only display the highest one hit. This really is a kickass option.