hey man - I fly Jet blue with bass about four or five times year. in fact it's my airline of choice for anything in the states and i have NEVER been charged or had any damage to my bass! great airline! I use the gage travel case - also just remember you MUST tape a key to the outside of the case so that they can open it and check it. if you don't do this you run this risk of them use a crow bar to get the case open. they often let me accompany the security people to make sure they close the case up properly. great airline and I have never had an extra fee to pay
Andrew