Just wrapped mine last night. I think I see in improvement in the heat. Haven't really tested it yet. That will be this week, as I ride home from work in 105 deg plus heat.
I used 1' tape from DEI from Checker Auto. They have a silicone spray that you're supposed to spray on after you wrap, "to help keep it from unwrapping". But I figured that the heat shields should do that. I don't want anything that might trap more moisture.
I wrapped down to the shield that covers the cat/crossover box and still have over half the roll left.