My Mylar Space Blankets (10 for $7) have just arrived from Amazonia.
So I did a test to see if they were worth a flip.
Here is a photo of my carefully constructed test apparatus:
I am testing two pieces of black rubber belly-pan material that came from the bottom of my car. The piece on the right is not covered by the Space Blanket and the one on the left is underneath the space blanket.
Here is a temp reading taken of my control specimen, pretty hot, huh?
This is a temp reading taken of my actual test specimen that was shielded by the space blanket, pretty cool, huh?
The measured ambient temp was about 84 degrees F.
Conclusion, Space Blankets are definitely worth a flip.
-AC