The salt water detectors I use are CZ-20 and Tesoro Sand Shark ... and I just got an Excal, arrived today, the batteries are charging.
Over the wet salt sand with single frequency detectors, I have found the concentric coils handle things better than the wide scan (DD coils). If there is a very high level of black, pink, purple or other highly colored, mineralized sand, then that may not be the case. In the black sand conditions on the east coast of the US from the mid-Atlantic and south that I've hunted, I'll take the concentric on the single frequency detectors, or use one of the water detectors.
For more insight on concentric and widescan over the wet salt sand read what Mr. Bill and SteveP(NH) say in this thread:
http://www.findmall.com/read.php?37,1244559,1244559#msg-1244559
My first forays over wet salt sand and knee deep into the water were with my Cibola. It screamed over the wet salt sand until I learned to tame it with a little less sensitivity and a little more discrimination and the smaller concentric coil. It still squawked on the wave flow, but I could detect between the in-rush and out-rush. It found coins and pendants in the shallow water and wet sand and got me hooked on wanting a water proof detector.
Cheers,
tvr