I think I paid $18 per 25sqft and I got the best deal I could have imagined. Make sure to clean the surface with a degreaser and then with soapy water. Works great, easy to work with, finished result is perfectly adequate. The only downside is it is easy enough to rip the top foam layer, but that’s easily resolved by not sliding around on it while installing. Lift your knees and feet and you’re good to go. Definitely has a stink for a bit, but that’s good. It is butyl after all. If it didn’t smell I’d be worried haha. 200mil thickness is about 2mm or so but with MLV on top, any thicker and you’d have an almost impossible time reinstalling interior. I can’t really tell if it’s made a difference in heat or temperature.