I actually don't have anything special, just a standard bag... But carrying so many Revs, spare rods, 1 rebar and a banner pole, I just distribute them throughout the bag and have NEVER had anything broken in 10+ years of regular air travel with my kites.
As for locking devices, I go with the old stand by... Wire ties (also known as zip ties).
The baggage handlers will sometimes want to take a look inside, especially on international trips... So, I go with what they use... They just cut 'em off, and put more on when they're done... I figure the less irritated they are, the better off I am.