I am about to upgrade from a 16 gb black 3g to a black or white 32 gb 3GS. I am contemplating going to the white one this time but am concerned about how they hold up (crack issue aside). Anyone notice any discoloration, yellowing, etc. I originally was going to go with the white but then looked at one of my older ipods (15 GB before the clickwheel) and it is horribly discolored. The 3G/S is obviouslly different material and the black has held up MUCH better than I thought (still looks brand new after a year aside from fingerprints) but I'm still worried. Also, because I assume it could be a factor, I use mine with a vaja retro slim bag and that's it. No screen protectors, back covers, etc.. thanks !