I would like to get some insight from anyone who may have used or has knowledge about PI machines. I have been considering one for a couple reasons. The first is to use on fresh water beach hunts to get past the black sand send hit the really deep targets, or to get the small gold. Depth seems to be the biggest factor.
Second purpose would be for inland coin and relic hunting at specific sites under certain conditions. Places like old sites with fill, or places that are pretty clean where anything else is out of range of the CTX even with the 17 inch coil on the best day. I would guess max depth with the CTX on a dime typically at about 12 to 15 inches if really lucky.
I would really love a waterproof machine, but only dive machines are available and what I gather is they aren't very deep. I have been looking mostly at 2 machines. The Minelab GPX 4500 and the Whites TDI. The 4500 has recently just been brought back on the market by Minelab with some improvements, and about half the cost of the GPX 5000.
One thing I can't seem to find any info on is depth testing on these machines with coins, rings, etc in good dry ground or sand. Any feedback would be appreciated, thanks@