3M 30-NF is blueish-greenish in color. We've been using it for years and havent had many comebacks with it. Most of the comebacks are from roof leaks that get behind the filon. It is very quick and easy to use.Several years back when I was looking for panels, I came across a refrigeration truck manufacturer in Atlanta. They used a 3M product to bond the panels. Never got the name of it, but I remember it being a blueish color. I wonder if this product provides the same rigidity as the epoxy. Looks like it would save time and money. May have to give this a test.