running it on my S3, for year or more now.
did notice it smoother (placebo effect??) when i first test it then it dissapeared into the norm.
i was sceptical, as whilst theory is there, the standrad earthing was very very good.
im a sparky by trade so I tested before and after results with a fluke, and TBH there was negligible difference.
but where it _may_ help is under load out on the road, and when temps soar ... but still not proven
if i took it out now, i doubt id miss it, but as its installed and hidden, ive left it in.
i made my own up with gold plated audio crimps and cabling.
its a cheap mod, that is removable, but dont expect much.