Hi. I am not totally new to using metal detectors, since I've rented them in the past. But I would still consider myself an "amateur" especially with the higher-end models. I am interested though in purchasing my first metal detector. I have done "alot" of internet research, and have talked with all the dealers. Now I should first say that I will mainly be using the detector in large open farm fields, with a high likelihood of mixed to high mineralization. I will also be doing some searching by some old homes, but mainly open fields. My uncle still plows these fields I speak of, so I'm assuming the soil is of good mineral quality. I have been struggling between either purchasing the Whites MXT, the Minelab Quattro MP, and even possibly the Fisher CZ Pro. I have heard alot of good things on all these machines. But I have decided for one that I'd definetly like a machine that automatically "ground balances" accordingly to the varying soil conditions. I don't wanna have to keep adjusting for this as I hunt. The one thing I'm also confused on is the "multiple-frequencies" that Minelab has on their units. I've been told that this supposedly gives "the best" depth of any detector? Again I'm no expert, so I was wondering if anyone could explain this further and if it even really matters, because I will most likely being running the detector in "all-metal" mode anyways in the fields. (I like to dig everything). So any suggestions would be greatly appreciated. Thank-you. Randy