I've got a basic unit and use it a lot both on the boat and for my work. We also have a Fluke with precision optics that costs close to $1000. One thing to be aware of is that if it has a laser pointer for aiming. Due to the optics you don't just measure the location of the red laser dot. If you look at the graphic on the side of the gun it will show the target size vs. distance. I don't have mine here right now but I think it is something like 3" diameter at 24" distance. If measuring a pipe hold the gun up very close. Also, if the engine is painted silver the readings are way off due to the emissivity. Any other color is generally OK.