I just wanted to let everyone know about my little project. I had the oh so common rear deck rattling in my 05 rs and it was driving me crazy. I ended up going to walmart and buying some foam pads. They are actually seat cushions. They are an inch thick and a pack of 4 was only about $4. I cut up two of these and put them under the rear deck. I also did a little dynamat in the front doors, between the two doors I only used one sheet. Between the dynamat and the foam, i have noticed a pretty significant improvement. I will be using the rest of the dynamat in the back doors and trunk, which should make an even bigger difference.