I have a friend who has toured many times to Europe from San Francisco. She has always used the industrial saran wrap with good success, leaves the wheels on so the bike will roll, etc. But, on the last few trips the airlines have really cracked down on wrapped bikes. Finally, this year she gave up and boxed her bike. YMMV, of course.
We made our first European tour (flew into Madrid) this summer. Our bikes were in cardboard boxes. All was fine both ways.