The sticky HP 35s plastic case

[McGruff]

I wouldn't expect any leather-looking cases to have the same results. This rubber-like material was used heavily for tactile reasons. Binoculars and scopes. I had the same garbage go bad on a shifter. If it was made to feel tacky, it could be the same material, and eventually it could begin to break down.

It's unfortunate that HP started using cheaper materials. The cases for both of my HP 11c's are in great condition, and are decades older. Well, the difference with the HP 35s itself is apparent too.

Great link Steve! Fun to see those cases and holders.