As usual, this board has helped me discover things I never KNEW I needed!! After reading a discussion on the Boston board, I'm now considereing a le Creuset french oven...Has anyone ever seen the white after it's used awhile? Does it discolor at the bottom, and is that why everyone seems to favor the colors? Also, what sizes do you find the most useful, and for what?? Clearly, I can't afford a set of these! Thanks!