I use a bamboo with a very small active area. I have never used it for anything outside of osu! so naturally there would be areas (the active area and where I rest my hand) that would experience more wear. You can see this as it turns from matte (unused) to glossy (most used), will this affect the functionality of my tablet? I'm assuming your tablet is like that since you have used it for four years, but as mentioned works like new, so am I only wearing away at the aesthetic value?