It does offer an increase of physical depth at about 1" Discrimination Mode, and up to 20% more depth on larger targets, especially in the all metal mode.
The Deepest Loop available for the White's Units when it comes to coinage and rings is the White's Approved Applied Creativity Loop marketed through Jimmy Sierra White's Dealers; The 12" Hot Shot.
This Coil has done remarkable in England on our Jimmy Sierra Tours and exhibited a propensity to Tag Gold Coins near Ferrous Trash thanks to its unique Dual Receive Coil Section and exceptional ground balance loop geometry. In my tests, I experienced up to 30% greater depth on coin size targets using this coil.
Still, my favorite accessory coil when searching with the DFX, MXT or M6 for Coins and Jewelry is the Bigfoot Search Coil. You can read about it on the Jimmysierra.com Web Site.... any specific follow-up questions, just ASK JIMMY or myself. Its a Great Coil and White's approved.