So I just purchased a pair of Columbia's that released in 2001 and I noticed that the bottom was in very good condition as far as yellowing. My Cool Grey XI's that released in 2010 are already yellowing a lot more and have never been worn. They are in a dark place where they can stay dry and...
I recommend going a half size bigger. I wear a size 12 and have Lebron 9s in a 13 due to the fact that I don't ball in them. If I was going to ball in the lbj I would go a half size bigger to get a snug fit still