Well as I never use 400 speed film in the course of business, it is really a moot point to me, but do have to add, the majority of film that is sold now a days is 24 exposure film, if I remember right, when I was working in the photoshop, over 85% of our film sales were 24 expsoure rolls of film and we were a pro shop and not a mass market store, and about 60% of our sales was ISO 200 film.

Dave