My first kydex holster wore a 1/4" scratch on my gun in 3 days.
My last kydex holster wore a 1/4" scratch on my gun in 3 days.
I like kydex. I have carried in kydex for many years now and so far, I have very little wear on the guns I carry. My Glock 23 has the most but, it has been carried the most.
My preferred holster for any of my carry guns is the Blackhawk SERPA.
My Comp-Tac, Blade-Tech and Fist kydex show a little wear on the corners and edges of the slide after a lot of use. My leather holsters wear more of the finish off and do it faster. I like and use both.
Please don't let this consideration color your choice of holster.
I have 15 year old Brommeland(leather) holsters that still retain the weapon while holding the holster upside down giving it a shake.
They are comfortable to wear all day, and conceal perfectly.
I may be biased though, I kind of like the look of holster wear on a trusted gun.