I will say this, I didn't notice a big noise difference (none of the rest of the cab is sealed yet after all), but adding dynamat behind the board before reinstalling has DEFINITELY made a difference in the thermal insulation of mine. That big square roof was always a heckuva solar panel, and this helped with the summer hot-head a lot.
I know it's still spring, but summer starts early in Texas...
"I just need to do a couple tweaks on my jeep, I'll be done in a couple hours." - gone 3 days