I have a $1000 dollar budget to buy a Whites MX Pro. I have really sought this thing out, and decided it fits my needs to compliment my current detector, a whites IDX classic SL. That being said, after the purchase price of the MX Pro, it will leave me roughly $200 to buy an extra coil. The MX Pro comes with a 10 inch coil. I want to know, under the circumstances, would it be better to get the detech 7 inch coil, or go with the detech 13 inch coil? In the near future I hope to have both.