I've seen those locally also (orange shelled, turbo looking things). The LFS
that had them said they were "trying them out" but weren't having much luck with them. Even though I wasn't acting like I wanted to buy one, they pretty much told me not to buy any - tough to keep alive. When I've gone back to that fish store, I've noticed there are a LOT of nice orange shells for their hermits to choose from now!
CluelessinNY... one thing about the coloration of snail shells - once your coralline algae starts taking off in your tank, it really doesn't matter what the shell's color is because it'll be covered with coralline within a few months. So that pretty orange shell won't stay pretty very long.