This is what i have been playing with based of coin and jewelery program.
disc.
B.C. reject:Off
Hot Rock Off
V.D.I. Selection: accept everything -95---- +95

Sens. R.X. set to stable or just a little hotter
Disc 88-92
All Metal 70-75

AUDIO
Tone I.D. Mode
Custom
Edit V.D.I. Tones..
-94 -95 and +95 set to 30 usually Iron , could be silver if deep and wraps around.
-93 -0 Set to 0
+1- +17 Set to 150
+18 - +29 175
+30 - +39 190
+40 -+49 200
+50 - +59 210
+60 - +69 220
+70 - +79 230
+80 - +89 245
+90 -+94 255 These can all be set to your likings. This gives me the spread I can hear and tell the difference between.
Freq. 2.5 normalize Works good in best data Also.
Ground tracking auto tracking turned off . Manually balance in clean ground about every 20 minutes or so.
Search
Ground filter 5.0hz
Recovery delay 80 -100 For trashy areas lower and slower
Sat at 20

Hope this will help some of you also. I have been to about 12 inch mark with close to stock size coils. Thats in ground that phases -93. Happy Hunting Yazoo