Everything I've found below 7" I was using a variant of Andy's HP coin program which is set up like so:
Reactivity = 2
Silencer = 1
TX = 2
8 kHz
Iron Vol = 0
Sens = 85
Disc = 2.3
Full Tones
Audio Response = 3
Keep in mind I'm using the 11" coil - the deepest coin so far was a Wheat at 9" (the length of a Garrett ProPointer) which only gave a repeatable high tone (in the above program) but IDed at 96. I couldn't get it with Reactivity at 3 but I could tell a difference in the "threshold" when scanning the target - makes me think there's more deep goodies at that house but if it ever stops raining I can go check!!!
When Reactivity is set at 3 or higher don't expect to get the smaller coins like dimes or small cents below 7" - but AT 7" you'll get them...don't rely too much on the VDI - go by tone instead. Dig those iffy targets in the beginning to see what the software is trying to tell you - many times it's sniffing out a coin within trash. If you get a good, solid VDI in one direction and then go 90 degrees to resweep and the VDI changes a little bit...DIG IT! If after you get a solid signal with good VDI then go 90 degrees and no signal...odds are it's iron...but not always! However, there are subtle differences in tonal quality with some targets which I can't describe with text so the best teacher on those iffy targets is plain ol' field time.
If you've ever replaced a caliper or a brake line on a car you usually have to replace those copper crush washers as part of the job. Deus LOVES those things! Anything round or round-ish and non-ferrous and this detector is all over it - sometimes steel flat washers ring in kinda hot but I feel that the next software upgrade may help with this...
I've never deviated from 8 kHz since the EMI in my neighborhood makes this the best search frequency at least here. However, I also haven't found any gold (yet) - although I dig almost every signal except iron. Good luck!