Jim,
Everyone is entitled to their opinion, but my experience with my GB Pro indicates it is an outstanding coinshooter. I uses the 5" coil, and am constantly blown away with not only the depth, but ID accuracy of the machine. The 5" coil is exceptional when working in heavy trash areas, such as one finds in parks. I have an F75 that I've owned for a couple of years. When I go to the parks, these days, the GB is my main machine. Last night, I went back to an old home site it had worked heavily with the F75. The GB Pro found coins I'd missed, including a '42 merc. I've been detecting for over 37 years and have owned top-of-the-line machines from most of the major manufacturers. I can honestly say the GB Pro is the most enjoyable and capable machine I've owned. If it has any negatives, it's the fact that it eats batteries. But, that is easily overlooked with the number and quality of finds. I don't think you'll be disappointed with the Gold Bug Pro.
Dave