Am going to be roaming around Europe with a concert tour and am wondering who would provide the best coverage (for a mobile data card)? In most cases, I'll have wifi/ethernet connections, but in the event that they fail, I'll need a REALLY reliable backup. My data connection will be extremely time sensitive, so it's gotta work well. I know that I can get these data plans through US service providers like AT&T/Verizon, etc. They are hideously expensive, but cost isn't too much of a concern. Reliability is more important. Anyone have experience with this? Can you recommend a service provider that would be better than others? Appreciate the help!