I don't think Flex worth that much, because...
I think, with this "fact", most of you will notice "how Flex works". ;)
Realistically there are 2 options here:
1. Get the alignment on your car checked. If you are doing such long road trips with a steering/suspension system that is not properly functioning, you are causing premature wear on your car which may cost you a lot more money in the long run.
2. Take the fitbit off while driving.