The 20-10's were designed to address the clamping issue some "fat-heads"
;-)) complain about.

I resemble that remark!
I have the H10-13.4S.

Not to be confused with the H10-13.4Y
I cannot afford to buy new headsets. I have:
2x 10-40's (my originals, they are still available but not advertised)
2x 10-13.4's
2x 10-13.4Y's