Um...well...AMAZING.
I just really couldn't believe I could possibly effect road noise in this car. And that has always been a major pet peeve of mine with it. But a noticeable difference now in how quiet it is goin' down the highway.
Also, music is much more clean, better frequency separation, more dynamic "punch" to it. Well worth the effort IMO.
Can't wait to get some trunk and rear deck done, and get the firewall a little covered.