I can only speak from my personal experience on the ground I detect which is on the extreme side of mineralization and heavy salt content, I run in GB tracking a lot, because of how rapidly my ground changes in GB values, my ground is very very variable and again it changes rapidly in GB values.
I do not detect salt water beaches, so I am speaking of inland extreme ground.
When I activate the mineralization meter on my Legend which was added in the 1.08 now 1.09 version, on the Left side of that meter is for Iron articles on the right siide of that same meter is for salt content, when I activate that meter on the ground I detect it literally pegs the left side at 10 bars of iron particles I.E (Magnetite) on the right side of that meter on my ground has 5-7 bars of salt content, in the 1.09 version I could get my Legend to calm down somewhat by lowering my sensitivity down to 15-19, but now since I have installed the 1.11 current version I can now run my sensitivity up to 26- max of 30 and my Legend runs very very stable on the same ground that I was once only able to get sensitivity to a max of 19 most of the time I was only able to run my sens to 16 now I can run a lot higher sensitivity than I was previously able to achieve, as I stated I have never detected salt water beaches with my Legend so I do not use the beach mode and can not tell you how a legend will or does perform on salt beaches, I will say that it runs very very good on highly mineralized ground, which is what I detect on 90-95% of the time