Bought Vaude karakorum (2010 model). Side bags can be attached individually (you do not wear the full kit) and pulled loose with a handle. The same handle to carry the bag with.
The bags are squeezed together with zippers. The bag sitting on the luggage carrier is detachable and use as a backpack (straps included). It includes raincover in sharp orange color which was a pleasant surprise.
The side bags have small compartment facing aft. The big bag on top (the backpack) has its compartment divided into a large and a little less. These are to merge into a single large compartment by opening a zipper.
Sustainability of the brackets and stability is not tested yet due. snow and laziness. However, Vaude generally good reviews of their bags and brackets so I foresee no problems.