I am the member that bought the Headhunter from George, I tried out the detector on a grass lawn using a quarter and 9 gram gold ring laying on top of the grass (not buried). I set the volume on high, tune with a barely audible threshold, and tried the frequency/pulse delay slowly through it's range from low to high, I get a little feedback and background noise on the swings but no beeps at all when passing over the targets. I also tried air testing with coil on ground and passing the items above the coil with the same results. I brought out my White's PI Pro and got solid hits on both the quarter and ring testing in the same location. I'm going to try out the Headhunter at a local beach this weekend to see if I can pick up any targets, will post back with results.
Thanks, Mike.