It's not only an issue of supply and demand, but also a question of knowledge... In other words, who's going to remember the dozens of different uniform styles that are being worn constantly over the years? Will anyone really try to collect (or care about) this stuff years from now? I believe there will always be people to buy the common player stuff, but like cards, this stuff is probably going to be really cheap to pick up in the future.

Unless its a star player, I'd wait for the value of all the newer stuff to go down.