If you're worried, then change the tickets. Vacation time is precious and preparing for it is hectic. You don't want to be worried the whole time preparing for the flight (then worrying during the vacation about the flight home).
If the peace of mind is worth the cost of changing, then do so. If not, just make sure your flight insurance is paid up. >:-)
I wouldn't worry about it myself. But tell your wife about your concerns either way.
Good luck.
Cheers,
Scott.