Success! The security check was uneventful, although the TSA guy threatened to run an E.A.T. test on it! It was one layer of plastic wrap and then the vacuum sealer bag - towels and in a temporary soft cooler. It was still warm when I landed and I put in in a pot of simmering water to hold temp until it was time to serve. Came out a little dry, but otherwise no worse for wear. Thanks for the advice, everyone.