Hey Andrew,
I'm in the opposite boat, I have the double d's and I prefer the smaller coil
for pinpointing, and depending on the sensitivity setting I believe it is easier to use than than
the larger 9x12. I run my sensitivity at around four notches.
I dug targets as deep as 11 inches with the smaller 5x9 coil. I detected for three
months with mosly the smaller coil and found 30.00 dollars in clad, many cool ornate finds, three silver
coins one was a seated dime a chinese coin from the 1700's one silver ring and one 14kt gold ring. I
almost forgot the V-nickel. If you've only ever used concentric coils the DD takes some getting used to.
You have to take these dd coils into your own back yard for your basic training.The coil needs to train
you, learn the familiar signs the soft tones verses hard signals. You can close your eyes and still know
when your getting a penny signal.
YouTube has some Garrett instructional videos you could watch to learn more of their possibilities.
H.H. Oh by the way, I just got the sniper coil for my Ace 350 so I'll be looking forward to some instructions from you!