I have been offered contract positions a few times. I have never taken them as they wern't always that long term. I have a mortgage so if it went to crap I'd be potentially up the creek. The biggest one was that my misses is a PhD student so she couldn't support me if needed.
One thing I will say as someone that used to travel a lot is, what do you think about being away from 'home' and more to the point, what does Carla think about you being away? If you/her hate it what kind of options would you have? Could you go back to 'normal' money?
Also, what kind of benefits do you get at the moment? Good pension etc?