i found the big coil to be tricky to handle because the ground is trashy with iron nails and other big iron objects.
version 3.1 is more stable and gives you a more silent search and to be honest, i like it allot!!! you can always go back to V2 when you like.
the used program is depends on the ground you are hunting on. i always use GM Power and tune it to where i like it, especially the tones.
i always use 12Khz, reactivity on 2, disc on 3,5, these are my standard programs as i tune this to the ground i search on.
with these settings i find hammered silver coins in a hole with nails and other junk, you really can pick out the goods,
as an indication : VDI 30-50 can be foil but also buttons, lead, thin silver or gold.
VDI 47 ring with a iron nail through it

VDI 55 i found a gold coin
VDI 70-89 is where i usually get the coins
VDI 92 silver coin (10 gram)
VDI 94 silver spoon
VDI 97 big silver pocket watch.
you will eventually hear when you pass a coin, with reactivity at 2 it is easy to hear if the object is big/small/broken up, coins give a punchy sound.
also you can swing the Deus really fast and hear everything it passes, as you get used to the tones you will swing faster unknowingly.
remember that the above settings and numbers are what my experience is on my field here in Holland,best is to just go out, turn it on, and pick up all the goods.
the deus is really a magnet for silver
o yeah, if you here a tiny sound that lets you think something is there but no VDI reading, DIG IT!!
the VDI shows only when the deus is sure what to show and lets you decide.