I loved the coil over dampers...you could adjust it to 32 positions on each side front and back, though I only did the front. on the stiffest ride you could feel pretty much all the bumps but I sorta liked the feeling, wasnt real jumpy. on the softest setting it was a smooth ride, unless you get on a horrible highway or street. It cost me roughly 1100 installed.
As for the deadening, there is never too much in my opinion, in fact, I needed more. It was raining yesterday and I really heard it on the roof, so I would have done that, but I heard nothing on the hood. Doing the wheel wells really reduced road noise. Think of driving your 6th gen and then hopping into a BMW, thats how noticeable the difference was. Plus with 4,000 underrated watts and a lil over 250 sq. ft. of cone area it flexes some major panels. I would love to have done more deadening but I didnt want to put the money into it.