I've mentioned this before, but I have successfully used my Compadre in wet salt sand, and even saltwater. Now, it's not a deep machine in these conditions, nor would I take it out past knee-deep, but it runs quiet and stable in both wet sand and water. The only caveat is it only gets 1-2" from what I can tell in the water. In the wet sand, I think it was hitting about 3". Now those don't sound like very impressive depths, but the stability is what was impressive. I pulled an earring back out of the water at about 2", which is a small target, but a valid target nonetheless. A week or so later, I hit the same beach with my Explorer SE, and a week after that with my Sand Shark. Both the Exp SE and SS were comparative depth monsters, but the Compadre will work just fine if you're just looking for recent drops (ie, shallow drops).
If I could justify a Mojave, I would love to try one out in the wet sand and shallow water. If the Mojave truly is a Compadre on steroids, I think it may possibly be an excellent wet sand machine. But, having the Compadre already, along with the SS and SE, the Mojave is not in my foreseeable future. I'd love to hear feedback from Mojave owners on trying it out in wet salt sand.
But to the original question, but the Compadre and Sand Shark are both great on dry sand.