i would say as far as deadening goes, it would do the job.
but it would probably like someone else said make your car smell like *** and a half for a **** long time.
2 months after i finished the eDead / PnS install in my friends car, and every single day it still smells like tar, and when it gets really hot out, the smell is more of a stench, and rapes your nostrils.