ive seen a couple of OEM headunits with all the bells and whistles im looking for in a new one for sale, and im hoping to find something that fits and keep oem look with red lights and everything.

is there a guide anywhere on what fits what model? and differences between each model of radio?
does anyone have one or have an opinion on the chinese ones being sold? and do you know which model and functions i can get for mk4 r32? im mainly looking for more EQ control and bluetooth. navigation, rca in/out and sub out are all things id like to get my hands on for future additions, but definitely arent mandatory.

any info on fitment or/and specs will be much appreciated!!