It's not a bad idea. If you're in an area with lots of trash, it could save you some time. I don't usually use mine while prospecting since it's easier for me to run a scoop of dirt over the coil and keep halving it until I see my target. I do have two different pinpointers and both begin to sense a .1g target at about a half inch in air tests. Shape and orientation of the target in the ground plays a role too. Pinpointers work better for larger objects like coins or relics, in my opinion.