I have the dry expedition bags on a set of Happy Trails SU racks for my 2006 KLR650.
I tried a mod to mount footman loops on the racks to use the loops as provided by Wolfman.
The footman loops were to big, so I just looped the straps around the SU racks on the boo.
The top rear loops I wrapped around the top bar of the rack.
I put my rain gear, an MRE, a water bottle and camera gear in the other one. Road about 60 miles here in Idaho, and so far so good.
As far as I am concerned, they are fine and will work well.