[Myrddin]

Same radios will work with the amateur licenses, so no need to trade up, though there re higher power radios once you have the licenses.

You have to be careful with the cheap Chinese radios. They are happy to key up on frequencies where they don't belong. GMRS/FRS has very specific channel assignments with power limitations and deviation limits. An "unlocked" Chinese radio might easily violate the GMRS rules. Likewise, it might invite a GMRS user to operate on ham frequencies without a proper license. Many large cities have instances of GMRS licensees coming up and giving the GMRS license ID on a ham frequency. Since there is zero training requirements for GMRS, many are unaware they are in violation of FCC rules.

[Reno89519]

Yes, most can so you have to program it carefully. That's a bit of a chore to make the lists of frequencies and repeaters, power levels, etc., but once done, easy to upload to all of the radios using CHIRP (https://chirpmyradio.com/projects/chirp/wiki/Home