I have read a bunch on the subject since buying one of the first off the line ATPro and YES it has found gold, silver and coins in saltwater surf. Falsing is the biggest drawback. To reduce the falsing set the Ground Balance manually to 15-19 (I found 17 works best for me) and drop the sensitivity. Then detect parallel with the water's edge and dig the repeatable signals.
True it is not the best detector for salt water, but it can locate targets. My choice detector for the Northeast is an ATX, for Florida and the Caribbean an Excalibur is my choice. Each beach can be different, knowing the environment and adjusting your detector can always produce the best results. No one detector can be the best in all environments. Make the best of what you have. Just think what detecotrists had to work with back in the 1960s and 1970s - the BFO, not waterproof and boy were the finds more plentiful and some fabulous keepers found, not to mention that most of the coins were silver!