I used it with a stock system so not aftermarket. Do you have any specific reason to believe aftermarket systems wouldn’t work? If they support android auto you should be fine.

ALL of the internationally branded phones i’ve had (mostly chinese) had compatability quirks with my aftermarket jvc head unit.

if well known brands like xioami or oppo wasn’t compatible, it seemed less likely that an enthusiast project would support it.

also: graphene is a non-start for me since it requires a pixel and i refuse to give google anything more than i already (unwittingly) have.