nmhunter, the MD20 is a specialized purpose machine. It is difficult to beat at finding tiny specks of gold... but the very tiny ones will only be detectable at about an inch (bigger pieces, deeper). Best of both worlds would be MD20 for specks, GB2 for pickers, AND an impulse machine for the biggies... deep. But now we're talking big bucks, too! Start with the 20, then add the 2, then save for the impulse machine. Terry