that insulation is better than mylar imo,you cant wash mylar the reflective stuff comes right off its a waste of money.Ive seen vids showing that flat white paint reflects just as good as mylar as well.been following your grow for awhile now. i was also planning for the same insulation foil (the one with the rough foil though) just wonderin if it does work as a reflector (i cant find mylar in my country). nice grow much respect!