Stones - UK vs. US Sound Quality? Anybody?

I know that I posted this before, but I don't have the time to go plowing through all of the Stones threads for the answer. More time has gone by so maybe now someone can answer this. Has anyone done sound quality comparisons (hiss, NR, EQ, etc.) between the same tracks from the US and UK versions or are they exactly the same? For example the US Flowers "Back Street Girl" and the UK BTB "Back Street Girl", UK Aftermath "Stupid Girl" and the US Aftermath "Stupid Girl", etc.

 

So far, I haven't been able to tell the difference between "models". Pretty sure they remastered everything with a track-by-track attitude. If they found a good Stereo version of Paint It Black, for instance, exactly the same thing is on Past Darkly and the US Aftermath. Same goes for, let's say, Stupid Girl. They're the same. So track-by-track, it's the same thing. The tracks that both US and UK versoions share, are the same thing.