Before you spend money on dynamat, go through your trunk with the side panels out and check for loose bolts and things like that.
You would be surprised how much of the rattle you can avoid by just tightening things.
"I'm not driving too fast...just flying too low"
-03 SB Cobra vert- 2552 of 5082 Born 02/25/03
90 7up vert - new project-07 DSG Focus -DD