FRS and GMRS work, but again, not type approved for that. And there are power issues.
And speaking of power, be very careful about car charging. Some folks seem to be buying cig lighter plugs that fit into the OEM Baofeng cradle, and they charge this way. But if that cig lighter cable is just a pass-through you may be applying too much power to your battery. It'll probably charge, but runs the risk of overheating and doing a Dreamliner. The input voltage should be 10v, so check to see what your 12v cable provides. Many of the ones you see around just provide what your DC system provides; I had to search hard to find a 10v one to use with the stock cradle.
There's a TYT cradle with a 13.8 v (max) cable that fits the UV5R, but some even feel that puts in a bit too much juice for optimum charging, although there's not a risk of overheating since it's designed for the higher voltage.