"Hope it works well for you!"...I'll let you know after the 3 year warranty expires, which appears to be hands down, better than the manufacturer:
Hehr Warranty.
FYI, I did not see any mention of performing a vacuum of the air space between the glass, in any part of Hehr's service manual....maybe I missed it, or....maybe they too regard it as unnecessary:
service manual.
Regards
Gemstone