Used the AT PRO exclusively in VA last week found some stuff, I did notice a difference in my machine in the heavy mineralization type soil, but all I had to do was ground balance often and slow way down and I still found targets. My biggest and and most brag worthy find all week was a eagle button at 12-14 inches in good sandy soil, good repeatable tones over that particular target every time I swung over it at that depth.. Also found a tip of a bayonet at about 7-8 inches in the RED RED dirt...lol Overall I was well pleased with how th AT PRO preformed in the rough soil, I did not find as many or as good as finds as many of the people there with PI machines and Minelabs it seemed but I was was well pleased with what I did find. I was also approached by many folks at the hunt asking how the AT Pro was doing for me seems like there is still quite the buzz on Garrett's new machine and interest and curiosity is still out there..lol