I don't have a pure white bag. I have a Marc Jacobs Stam in White Chiffon, which is off white, kind of cream. I haven't worn it yet.
I have always stayed away from white bags. It has to be the perfect bag or they look cheesy, in my opinion. I really want to buy a white bag this year, though. I think something more on the casual side, but not sure. I worry about keeping them clean and really white, too. I am curious to hear from others who have and wear white bags on a regular basis.