I've been using the Ortlieb Trunk bag successfully in conjunction with my panniers on a Tubus Rack. I am now planning a trip using my road bike with a seat post rack using the trunk bag. Has anyone used this product?
Yeah, I don't have a seat post rack yet, so I have some flexibility. The Kwikfix mount works really well so I think this rack may be just the ticket. Otherwise, you are correct about the different mounts.