I'm a fan. I've used them on several bikes now. They are rugged, simple and sturdy. You can see my setup in a ride report here
. They are not waterproof so I use these
for my clothes and roll-top waterproof bags for tools and other stuff. My shoes and jacket liner go in a waterproof bag on top. The design places the weight over the seat with some transfer to the frame via the Dirt Bagz rack. On the trip described in the linked ride report I encountered some heat issues from the muffler on the first day - a sharp tug on the rack moved the whole deal out enough to create some air space and there were no other problems on this trip.