Field experience:
I use my 1266's for relics, period.
It has a dual disc with a toggle (that 'trigger' thing sticking out from under the chassis). Depending on soil conditions, I run mine 0 (Disc 1) and 3 (Disc 2), although show me a relic hunter who's passing signals because of disc, I'll show you an inexperienced relic hunter. You should be digging it all. Disc-3 will cut a deep belt plate, minieball or dagger right out of existence. Relics, especially battlefield stuff, means there's a real potential for finding stuff in that 12"-16" deep range, even deeper.
A lot of your 'coin shooters' started out as relic hunters but gave up and started chasing pocket change after their tenth 16" hole that yeilded a tractor bolt.
Also, these can be chattery, which drives some people nuts. You'll learn what constitutes a signal versus chatter.