I've had my Gold But Pro DP for just on a month, with 2 weeks of that time being used at saltwater beaches using the 11"DD coil. I was impressed with the depth achieved by the GB, particularly in all metal mode. Yesterday, I was using the Gold Bug at a site near home (no beaches, sadly) and had the 5" DD coil fitted. The bettery level was down to 1 segment, so I wasn't expecting to get that much depth. Got a signal, probed, and the probe hit the coin at 3" (measured) below the surgace of the ground (about 4" below the surface of the grass). My first thought was that I had just hit a small rock, but when I dug the plug, a $2 (Aussie)coin as at the botton of the plug.. Our $2 coin is 20mm in diameter, so, not what I would call a large coin. I was impressed with this depth with the battery "on its last legs". In disc mode, Sens at about 82. HH