Astrolar Blankets for a DIY tent?

I don't know if any of you have seen or used astrolar blankets, but I was wondering if this looks like a good idea for a DIY tent cover. I'm thinking of making a 4'x4'x6.5' metal frame for a tent, and wrapping these astrolar blankets for insulation, light tightness, and reflectivity.



They are like $14 each, and they are 7'x5' blankets.

yeah there prett good my freind uses for the same thing . were can u find them?

REI has them check -> http://www.rei.com/product/407106