I'm looking for a beach detector that will handle old pre to early 1900's dock sites that are really rocky with black sand and lots of decomposing iron. I'm not sure the Minelabs would do well with all the big and small iron at these sites along with the Fishers. I'm wondering about the Whites Beach Hunter ID. How well does it handle the iron and how quick is the recovery speed? Does it handle the black sand and hot rocks without to much depth loss? Thanks for any help!