Originally Posted by maxcichon
The addition of the capacitors is for cars with the rear subs only....

Max, this is an interesting comment...
Maybe I didn't read the original Capacitor thread in it's entirety.
I did the Cap Fix on my Roadster with the Stock HU (No Nav), and never did hear/feel any actual improvement.
I'm guessing the Roadster dosen't have the same Sub's as those found in the Coupe.
And for anyone who's interested, I think the Stock HU sounds chinsey, any replacement would show a marked improvement...IMHO...