Hello Geoff,
apart from cosmetic reasons I prefer the non-sticky version as well. My own sweat shouldn’t be the reason as it’s never occurred on my other Instruments. I hope it’s going to stay relatively clean now, if you zoom into the photos now the dark spots that you seen on each button are apparently a reflection of me holding the phone. I’ll attach a photo so you can see how they looked before the treatment.
Hope to find sth now to give the ends back a bit of a shine.