I 've worked with elk and deer hides for over 35 years
both commerical tan and brain tan
I just dicovered german tan about ten years ago

the main difference between deer and elk is in the size and thickness of the hide,commerical tanned deer and elk have the pretty much same texture and softness

a brain tanned young elk is very much like a large mule deer buck
and brain tan depends on who tanned it

german tan is like somewhere in between brain tan and commerical
tan and is an unique piece of leather I really like it, but like any 18th century guy I prefer brain tan or elk depending on the project