timreid - when you say "under" the door panels are you talking about the door "skin" (the area that you have to remove the moisture barrier to get to) or are you talking about the surface right beneath the door panel?

I had a Miata which I had applied multiple layers of Dyanmat to the door panels ("skin" of door). It had a major effect on noise reduction.

I personally would not go with the spray products (I used these in the trunk of my Miata). They tend to be quite messy. I think they are better used in areas that don't have so many moving parts (ie hard to reach corners of the trunk etc.).

I think it would help to mulit-layer Dynamat the roof area.