I'm not an expert on this, but my friends and I will be going to IM Frankfurt from Michigan. What I've found is depending on your airline taking it on the plane is the cheapest route. Also make sure you check all the rules and regs with your airline. I'm flying with Luthwansa and they charge $150 each way, but you have to call ahead and secure the spot for your bikes because large items like that are first come first serve.
As far as bike cases go I'm still working on that part.
Good luck in the race and for the trip.
Chris

Sci'Con makes an attractive line of products. I've gone with a softshell option but you can find their Aerocomfort Evolution hardshell option which is popular among those who've gone the hardshell route.

http://sciconbags.com/en/bike-bags/aerotech-evolution.html

It is however for a single bike so you'd need two of these. I am not aware of any manufacturer who can hold 2 bikes.

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"Train so you have no regrets @ the finish line"

I just picked up a Thule Round Trip Sport. It was the best value in a hard shell case that I could find.

X2 on the Thule, I got mine out of craigslist super cheap, I have used it maybe 4 times and I have no intentions to change it.

With both of you going, it is probably worth it to look at the TriAll3Sports VeloSafe II. http://triall3sports.com/cases-bike.php

It can hold both bikes, and at least 1 set of wheels.

If you are lucky and they only charge your the bike fee, you'll get a 2 for 1 deal. It will be over 50 lbs, so they might double dip on charges, but I had good luck with mine.

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