Good afternoon, oft time lurker, sometime poster. I am an enthusiast that details my own cars and on occasion those of a friend or two. I have a Rupes 21 and an assortment of the Rupes pads, blue, green, yellow, white and some UHS pads. I am finding that the pads are starting to break down ie disintegrate. As I am using them, I find that small bits of the pads are flying off. I hand wash the pads and allow them to dry after each use. Is this normal? Do these have a limited shelf life? By the way, I used them on a buddies 2008 Mercedes S550 this past weekend. He parks it outside 24/7 here in San Diego. It was regularly washed and occasionally clayed but never polished by machine. Wow! The car is huge and it took about 7 hours total, inside and out but the car turned out great! Looks like it was glowing after I finished up. Incredible paint on those vehicles. This is a great site, however, I am hooked on Autogeek, spending way too much over there. Phil