No idea how true this is as we did not order our new Bennington with the glacier white interior. I know on friends boats over the years, the ones that had various versions of a white interior usually had some discoloration over time: just dirt, spills, sprays, etc... Nothing major, but enough for us to not consider going in that direction.
The down side of that bias is that the glacier white with certain color combination Bennington's is an amazing look. It can really look plush, or nautical, or even sporty, depending on the color combinations around it.
Probably not very helpful to your decision making process, but I wish you luck in making a good choice.