@ Rick, Sorry but the Elite is NOT fixed GB, but is fully automatic all the time.
(page 7 of user manual :-"As soon as the Sovereign Elite is turned on and swept across the ground,
the ground mineralisation is analysed and then compensated for by
the microprocessor. This ensures that the Sovereign Elite can locate
targets deeper than other units, due to its automatic
compensation of changing ground conditions".)Hence Auto GB
(From the user manual Spec page, "Ground Rejection: Automatic Ground Tracking")
Ground balancing is refered to in many ways but is basically the same, AutoTrack, Ground rejection, Ground Tracking, Digital filtering, Auto tune and many more depending on the manufacturer.
All my sovereigns that i have, had and tested are ALL deeper in All metal than in Disc mode
In Ground that has little to medium iron the sovereign will be just fine, in high iron content aswell, but till you get used to it and what its telling you it will be more of a struggle
If i had the cash i would have an Explorer SE Pro any day, once learned well i think it will be hard to beat