Spent some time Saturday listening to my Tejon. I was running in all metal accept discrimination mode. By that I mean, my main discrimination control was set to min. I've got to say I was almost 100% accurate in identifying iron from other targets. I set my alt discrimination to about f in foil, so when I found a target I would guess if it was a target I wanted to dig or not before checking with the alt disc setting. There really is a difference in the sounds. I knew the penny and dog tag were something I wanted to dig before switching to the alt setting. I really believe you have to put some serious time in to come to this point of a relationship between man and machine.