Even still he is knowledgeable but using a nickel isn't a great test other than to show which machine is deeper because nickels are strong conductors. Similarly comparing a squash can to a quarter or penny.

I'm not disputing the fact that those machines can detect a nickel at 16", my Tejon with 10x12 hits a nickel at 16" (not in the salt as gb isn't suitable for salt).

I'd be convinced when someone takes a thin gold chain and see which machine wins in the wet salty sand or surf.

Spending tons of money to hunt nickels doesn't make sense to me to be honest. Not seeing the point of that test.