33L Rackless Loadout
I recently completed a 1000km trip with these 18L (9+9) Rhinowalk rackless bags + a 15L universal tail bag. The trip was into central Australia, so they were put through a fair stress test.
The Rhinowalk rackless saddle bags required some creative rigging up, only possible if you have the rear passenger handle attached to anchor them to. All other anchors ran under the seats. They do come in bigger sizes but they might not fit as snug as the 18L option.
The biggest down side was that one of the buckles was rubbing the bike. I have a wrap on so it protected the paint but it's something to be mindful of.