The first time I tried Edco foil I was astonished by how easy it was to work with. The copper itself was thinner, and folded over the glass easily. <ding!> If I slowly worked the foil on deep concave curves, the foil might split from being stretched too far, but more often than not, the foil would stretch and not break. <ding!> The adhesive strongly adhered to the glass, and there have been times where I've had a roll of this foil open for over 2 years and the adhesive didn't dry out or lose it's stickiness at all. <ding! ding!> Over the years, Edco foil has been nothing but consistently excellent. I could be completely out of foil and I won't buy VentureTape if it's the only brand available. I'll wait to find Edco. Thankfully there are several places online that routinely carry this foil as well as my favorite local-ish supply shop.
It wasn't until this past year using the power of the Internet and a little digging that I found out that both of these copper foil manufacturers offer their products in different thicknesses. From what I can gather, the VentureTape is typically stocked in 1.5 mil or 1.25 mil. Edco seems to be either in 1.25 mil or 1 mil, but all three thicknesses are available from both brands. The thinner the foil, the easier it will fold and bend, so the easier it is to work with. It may also be the difference in the type of copper used. I've seen product descriptions for Edco that say they use "dead soft copper." This is the softest copper available and the hardness or softness of copper has to do with the manufacturer of the copper and the annealing process they employ. I would wager a guess that VentureTape does not use "dead soft copper" because it feels much more rigid when I work with it.
Are there other copper foil brands easily accessible out there, and what have you worked with? I'm always open to trying new brands, I just haven't seen any locally to try. If you're interested in hunting down some Edco foil, let me know and I'll be happy to help you find it.