I have one of these, and they work really well on the rear rack of a C14. It's not so much the added space, it's the convenience of having a space you can get in-n-out of quickly and simply...sort of like a tank bag that you can only use when you stop. Great for drinks, a cheap camera, a hat (for when the helmet is off), earplugs (don't need access to those while underway), etc., etc. The rain cover has a drawstring that you must use, or it will blow off. Attaches to the bike quickly, has two outer pockets and two "wraparound" zippers that allow the center compartment to expand.