I backpacked in Europe and Asia in 1970 with one of those packs with an aluminum frame and it broke in Turkey and trying to get it fixed was impossible so I hear you on frames and damages.
That's why I'm interested in soft bags instead of Jesse's that I used to own. One low side and major repairs are needed plus the chance of doing damage to your legs with the hard bags.
But at $650 I need to be convinced
So getting back to the backpack theme, they have some kind of internal frame to keep them out of the rear wheel?