I have not had any trouble with this machine on wet sand. Not sure why you would be, but not been the case here. As far as the deeper machines, sure but at what difference in cost? The reverse discrimination functioin is also not something I concern myself with, but for the times I have tried it, it seemed to work fine. The dual tone also did not bother me or seem to delay response etc. All that just points to the same thing that it always does. Not all machines will be correct for all users and uses. Patience, comprehension and a lot of other variables will always come in to play. Research as much as possible, test drive what is available and decide from that. Buying a machine that you have not had a chance to run yourself is always risking money based on someones opinion, question is, how much can you afford to risk and for what gain?