It will come down to your personal fortitude blowfly. As with any detector, the more open you have the discrimination, the more targets that you will hear and the better informed you will be. Most times I have the all metal mode turned off, but if the ground is infested with iron, you are actually going to find more good targets if you run in all metal. This allows the detector to reset after each target faster, so reduces the chances of a target being masked. It will also better inform you that if an iron target is close by, then you can hear it and be aware that it could be dragging down the numbers of a good target, that you may have otherwise walked over because it wasn't in the number range that you were looking for.
Yes, you will learn the detector faster by doing this, but it will come down to your personal choice as to how long it will be before you become irritated by the extra noises. Some folks are quite happy operating in all metal all the time, so it will be up to you as to what is best for you.
Mick Evans.
