I used a product called Fat Mat and you can find it on Amazon. It is a lot less expensive than Dynamat, and in my opinion, it is just as good as Dynamat. Now, asking someone the "best" sound deadening is the same as asking the best cam or exhaust system; you are going to get a bunch of different answers. I probably put over 225 sq feet of Fat Mat in my car, basically putting it on all exposed metal in my car: floor, sides, roof, hatch, doors, etc. Now, I did run out of Fat Mat and I put Dynamat on the interior door skins while I put Fat Mat on the interior of the door on the exterior door skin.
In order to do it right, you need to gut the whole interior. Not only that, when I put in my carpeting, I put down extra insulation and my carpeting has "mass backing". That is a rubberized coating on the back of the carpet. Got the carpeting from stockinteriors. Now, adding all this sound deadening will add weight, but I wanted a quiet interior.
You can see my Fat Mat install in my thread for my Redline Goods Interior thread, post 21.
There are a lot of threads discussing this, so look through them and see what matches your needs.