I didn't even do any in house testing before i went out to one of my old homestead sites that my brother and i have hit already hit twice this year and have taken a couple goodies out using couple of diff. machines. Did pretty well, this field was just plowed a week ago so it's soft and spongy. I didn't get any "get the backhoe" signals but i dug a ton of brass and copper items. Did get one big penny, 1831, and one indian head, 1902. And one wheatie a 1912s. Did get five flat buttons and a huge thimble. I Know why i didn't find a lot of change,,, they musta spent all their money on shotgun shells cause i found a boatload of them puppies.. I did notice that some small brass items would get a little choppy but this site is loaded with iron and nails. I noticed that the depth really increases if you can run sens. all the way to 20, and i wonder if once your ground balanced you can set it a little negative to run hotter or not. Didn't play with the settings a lot , i just wanted to hunt today. Overall i think i'm gonna like it for this type of hunting, do i think that it's gonna take the place of my expl.? No, but i think it's gonna keep some of the other manufactures up at night...Gonna give her another run tomorrow and play with the options a little more. HH....