Having owned a Pofung UV-30, the clone of the Radioddity GM-30 since about Day one, here is my best advice:
Buy two Baofeng UV-13s for about $22 each, They are the Ham Radio version of the Baofeng GM-15, which is also a clone of the GM-30. These are already open and can operate on GMRS.
No firmware muss and fuss! USB-C charging and Tone Scanning, too!
With my purchase of my UV-13, I retired my TYT TH-UV88, which is really long in the tooth!