I used the blue tex radiant barrier, it seems like a better product from a better company that doesn't tell lies about insulation value. It does make a big difference in radiant heat, I tested it some while building my shop and measure a 35F difference between the inner surface of a wall with it and one without it. Since I wrapped my building frame up tight with it before installing the furring strips and metal it sealed out drafts and I have a 1" air space between the metal and the radiant barrier/framing, which probably does something from an insulation standpoint. Besides sealing out drafts I doubt it does very much in cold weather. It also comes with nice tape on the edges to seal between sheets, you just peel off the tape flap covering after install and smooth it out.