Just a reminder of the worst case scenario!
i was just going to post that one, but i see you got ahead of me.
a real flight case is much more protective than a regular hardshell case if it fits right. yes, it's much more expensive, but they're made to withstand people flinging the instrument, sometimes down huge drops.
some airlines are supposed to let you bring it into the plane with you in theory, but i've read some posts at AGF where the plane crew knew nothing about that policy and gave them the chance to either not fly or put it in cargo.