Well , last night I decided to see how well the reflectix worked.

I cut and wrapped the the insulation around the water bottle. Cut circles for top and bottom. Duct taped the seam and bottom circle. I just pushed the top circle in the cylinder.

I put out one bottle w/insulation and w/out. ( Out in the open above snow and in the wind.)
Filled both with cold tap water.
Put both out at 9 PM . Checked them at 8AM.
The over night low was 5 deg.
When i checked them in the morning it was 9 deg.

Bottle w/out insulation was almost frozen solid except a hole about the size of a quarter running through the middle.

Bottle w/insulation had a thin coating of ice on the walls and about an inch of slush at the top. About 80% water.

It works. Now I want to try the blue foam.
Although reflectix would be less bulky.