Hammer, every machine you have mentioned from FTP is the Fratbros in house process shared by many FTP detectors. These are, the Fisher F5, F11,F22,F44, Teknetics Alpha, Delta, Gamma, Omega, Eurotek, Eurotek Pro, Bounty Hunter Gold, Platinum, Lone Star Pro, Quick Draw Pro and Land Ranger Pro.
All are going to give the same detecting experience, only offset by the options and coils used. The newer LSP, QDP LRP from Bounty Hunter, Eurotek and Eurotek Pro, and F11, F22 and F44, plus the Omega 8500 uses the latest process to come from FTP, and wind up using less battery power to accomplish more options without sacrificing depth.
It all comes down to the options you desire. And FTP has given many in the fields available, with the new 8500 having pretty much all of them.