I have my manifold wrapped, turbo wrapped and the first section of down pipe before passing by the shock tower. I did it to reduce underhood temps, which it drastically reduced to almost say +10-15* above outside air. Even with the stock turbo, overall turbo efficiency I would say went up, as egt's per boost psi went down.
Without it, I was 650* @ 65mph with 3-5psi of boost. With it, I am 600* @ 65mpg with 3-5psi of boost. These results are based on the same stretch of road, although small change, it was a change.