All of the ACE coils are sensitive to small objects. Even the 9x12 will easily find BB's.
But... with the lower conductivity of gold and the often hotter ground in those areas, I can
see how a dedicated gold machine could help.
But I was really surprised at how well the big 9x12 coil hits on small objects. Even tiny
slivers of metal will set it off. BB's hit real hard on all the ACE coils. I've found single
BB's and tiny slivers of metal using the 9x12 coil. It's really not that much less effective
than the sniper, except for seeing more objects at once naturally. More depth too as
long as you keep a decent swing speed.
You can use the pinpoint mode on the ACE 250 as an all metal/non motion mode. I do it quite
often. You want to make sure you are not de-tuned though. When using the pinpoint mode,
the sensitivity control has no effect. It's always full blast unless the machine de-tunes on a
button press. It seems to adjust the sensitivity right when you first press the button, and then
it holds it until you release. So if it de-tunes, just re-press the button a time or two until it
sounds hot again.