If I were just going for deep targets I'd have to go VCO mode in discriminate with a low discrimination setting.
VCO gives very good depth feedback when pinpointing.
Run sensitivity as high as is stable. Threshold to just hear. Tejon does not benefit much from super tuning although many of the other Tesoro detectors do.
I spent some time with the Tejon comparing targets in discriminate and all metal and found that targets I barely heard in all metal, would beep in discriminate, although sometimes iffy. Not much difference in ability to find a target either way. If you generally prefer hunting in all-metal, then do what you are familiar and comfortable with.
Neutral ground balance if hunting in all metal.
Very slightly negative on the ground balance if running in discriminate mode. Search this forum for Monte and power balancing to find discussions on why slightly negative is the sweet spot with a Tesoro. If you go too negative, you get false signals that chirp and do not repeat well, so set it just very slightly negative and check it fairly often.
Cheers,
tvr