I use a BH Sharp Shooter II, similar to the 505, minus the depth indicator. Personally, I like to hear all targets and decide for myself what to dig, rather than have the machine decide for me. Bounty Hunter machines are good coin shooters and are pretty accurate in coin ID. But keep in mind there are a allot more great things to find in the ground than just those 9 common targets listed on your machines target ID, so don't buy too much stock in the ID. I think Notch/Auto Notch acts as additional discrimination on top of DISC, not sounding on all possible targets (which I guess is the point of it). And I have noticed a slight delay in recovery time between targets, or delay responding to a single target in Notch/Auto Notch. I prefer DISC mode, with the Disc knob turned fully Counter Clock Wise, and can run Sensitivity at about 3 o'clock in my soil conditions without falsing. I also have a hunch that cranking up the disc knob can cost you depth.
