Hi Pescadore, I too have a Whites DFX with it's two frequencies and love the Infinite number of programs that you can plug in. If you were to consider a Different coil you may find more success in finding those Deeper and Older Coins too. Check out Gary12penn at the You Tube for a eye opener. He used the Standard 950 coil also and then experiment with different Brand coils and sizes and programs too until he increased his success with old Indian Heads, old Silver etc. with out the new expense of a new machine and a new learning curve. I know he tried the Mxt. but stay's with the DFX. Good Luck and Future Success. Budwiser