Anyone have any experience with VacuMax glass (or any other vacuum insulated glass)?

https://www.vitroglazings.com/products/specialty-glass-applications/vacumax-vacuum-insulating-glass/

From what I understand it’s two thin sheets of tempered glass, spaced apart by these nearly invisible spacers, and all the air inside is sucked out to create a vacuum. VacuMax boasts R-values up to R-20. I have a small sample VIG panel that’s R-14 / U-0.07. Obviously, that’s just center of glass, not a whole assembly value. The rep who came through said that cost is in the same ballpark as triple glazed, but obviously this can be much thinner which is nice for replicating an old-school steel window look.

It just seems too good to be true, which makes me immediately skeptical… Would love to hear what other know about this stuff.