They seem to be pretty damn good and are always cutting deals and working with new products. Depending on your goals if road noise or wind noise is your concern you are sort of stuck. You will quiet it down some by applying some mat to the top of the fender wells, the floor, and the roof.
I ordered a roll from RamAudio. No asphalt and people who use it like it. I was looking at the dynamat extreme, but it's expensive and I am not sure it's worth the extra money. I am not trying to duplicate a Lincoln town car, just quite the car some. Also, they shipped the roll for $14.00, about the same as Jegs.