I don't think they'll be less expensive, but the selection may be better. I'm going next week to Paris/Brussels and I may pick up a new longchamps. I am not too crazy about the spring colors though.
However, someone with better idea of Asia v. Europe prices may be able to tell you.
I think the build your own bag is a neat idea. I have something like 15 les pliages. I could have bought a small chanel for the same price!
I'm wondering the same thing about Cartier -- I'm wondering if I will really save enough in Paris to make it worth an hour in the store next Friday or just go to my local boutique where they are not snooty and quite patient with me.
There is the sales tax issue...
lala