The Uhaul mattress bags are packaged real tight, I buy two, one for outgoing, one for coming home. I remove my chain, unscrew the rear derailleur and ziptie it to the stays. I remove the front disc on the way out. Remove pedals, turn bars and hope for the best. I've had more damage from the TSA pulling my bike out of the box and trying to re-insert it. The bag has resulted in zero damage in three international trips.

Plastic bag allows the TSA to see everything without have to unpack the bike.
Baggage handlers see it's a bike, it's not protected, they handle it nicely.
I watch them from my seat, a bagged bike goes in last on top of everything else.