Wow! Fantastic trip, I'm very jealous!!
I don't know what's best, exactly, but I'd prefer a hard shell case. Airline luggage handlers aren't required to actually possess ALL the normal human chromosomes as condition of employment, and often act like it.
The other thing to do is make sure you understand the luggage size requirements of your airlines, as some of the larger bike boxes are "over-sized", which is *very* expensive to bring along. Here's a good starting point for your research:
http://www.competitivecyclist.com/ro...-cases.42.html
A good box is expensive, but then so is a ruined trip from a broken bike. The Serfas box looks like a reasonable compromise in security and size and cost.
Cheers!