Per the letter of the law (FCC Rules) the only radios permissible for use on GMRS are radios that have the Part 95 certification for GMRS. This is either the current 95e or the older 95a (grandfathered). So, unless the radio model in question has one of those certifications it is not legally permitted.
As you read in this forum you will find that many people use higher-cost, higher-quality commercial grade Part 90 radios. Many have stated that there is not a single incident that can be found where the FCC has cited someone for using these higher quality radios. The FCC in one document indicated it was not their intent (when they revised the rules) to exclude the use of Part 90 radios in GMRS, but they have yet to make it officially legal.
No, even an licensed amateur is not permitted to legally use a radio in the GRMS that is not type certified. There is no radio made for amateur radio that is legal for use on GMRS, although many can be ‘modified’ to open it up for GMRS, but even then, it is only permissible to be done by and for use by certain individuals.
I may have missed this in previous posts, but are the Baofeng radios technically legal on any frequency range? GMRS? I'm seeing what I think are mixed views on whether they are GMRS legal, or not. They are popular with 4wd and car clubs, and I know many are using them, sometimes on GMRS frequencies, without a license. I've cautioned them on using them and also about using GMRS frequencies without a license but none seem to care. So can a licensed GMRS user communicate with them on a GMRS channel legally? And it looks like they are not technically legal for FRS, partly due to too much power.
I guess I'm confused as to why they would be permitted to be sold if they aren't technically legal at least somewhere. That'd be like an illegal drug being permitted to be sold but not used. Then again, with the federal government, nothing really surprises me.
Maybe legal for licensed HAM operators?
I just thought of one use that should be 100% legal. They receive FM radio! Lol!