The new extreme stuff is very easy to install. You can cut it with a box cutter and it sticks to anything. The old dynamat was crap, you had to have a very clean surface. I paid $175 for their big box and it was more than enough to do my hatch (double layer on the rear wall), the floor pan under the back seats and a layer on both door skins as well as the inner structure on my old Talon. I still have probably half a sheet left!