I recently bought a Frost River Gunflint Trail, which got it's first outing on the Friday night ride last week. It is well built (cotton duck, leather and brass fasteners). Holds, so the manufacturers say, 25L. the reason I went for that rather than a Carradice, is that the FR is sqaure in section, whereas the Carradice tend to be rectangular, thus stick out further either side of the bike (and I think a square bag is easier to pack than a rectangular one)