Hey Merc....Great lookin ride....I'm new to the Cortes, having sold my XLT to get this machine, I set the sensitivity at 8-9...discriminate at Foil....everything else at , such as switches in the middle....I find the ID number is a good indicator asto whats down there....it rearly shows anything but a zero if the target is iron....just watch for the ID number to move off zero, and dig!!!!!..and learn how to use the SUM switch!!!!..it's a good machine...I'l going to get the Cibola also, just for relics....Hope this helps, Steve in Tenn.
.....with Steve about most of what he posted. But, I would not constantly be watching the Target ID! Instead, learn to listen to those subtle difference is tones. That machine will be talking to you in its language, and that's a language you really need to learn.
After you hear what sounds like a good target, and it is repeatable as you swing across from side to side, then use the Target ID as a means of confirmation of what your #1 Discriminator (your brain with input from the Cortes through your headphones) is telling you. Then and only then, confirm with the meter.