You can find a lot of goodies with the stock coil.
Pinpointing is pretty easy once you get the hang..
Practice with coins on top of a box or whatever to
see where the coil position is vs the coin.
With the stock and also the larger 9x12 coil, you
usually use the "pullback" method. That is, you center,
and then pull the coil back until the tone quits.
At that point, the coin should be right in front of
the inner coil.
The sniper coil is different, and has an "X" in the
middle that you use as the pinpoint marker.
I have all three coils, and use all of them depending
on what I'm hunting. But I agree, the sniper is probably
the most fun coil of the bunch as it's so fast and precise.
And it is good to 5-6 inches. The stock coil is probably
good to about 7-8 inches. The 9x12, I'd say about
10-11 inches.. Using a quarter for all tests...
Course, ground quality will vary the depth you get..
MK