if u wan soundproof, then forget about superlon...superlon are good in heat insulation..no good in soundproof..
use those kapas under ur carpet..those are really good...u can get it in acc shop..but it's not cheap

dunno wat it call..but it's a layer of something like kapas that was being compressed..wait..i take a pic for u...

this 1

good for soundproof....

rattling? find where the rattling first la....sometime just screw loose or something hitting anothing only....this kapas wont help much if ur car metal rattling....sometime u only need dound dampening but not soundproof......

er, i actually using the real bitumen for roof sealing..been applief for nearly a year....never fall...but i admit it's a bit messy than other material cos it's more sticky and more liquid compare with other material...

but 1 fact i found is my bitumen actually perform better than many many of the brand outside..included the material sold in forums....tested and proved by some soundproof customer.....

easy to remove? every soundproof material are not design to removable...:> so wat u think?

unless those oem kapas-kapas thing...

none of them as i know..btw, somebody mention before getting those Van rubber door lining to add to our car(double layered)..and the wind noise will be reduce...but door are harder to close...