The Safe and Sound isn't bad but there are better Roxul products for bass traps. If you check out the technical specs for sound absorption, 3" S & S boards have a Coefficent of 0.52. A better board would be the RXL 60 with a coefficient of 0.78 ( basically a denser board) which is 50% more absorbant than the S & S.

I was able to find some discontinued high density RXL 120 which I used for my basstraps.

John