I have
Zing Action Straps on 3 bodies (and a knockoff on the other body!).
UNFORTUNATELY, the Zing brand now appears to be part of the Tiffen Group, and they have discontinued that strap! I got the very last one in stock (in NY) a few months ago - and very glad I am too because they are very comfortable and long lasting!
OTOH, I have quite large hands and can only just tighten them enough to "fit" me (especially on the K-30 & K-70) - people with smaller hands would probably find them quite loose.