George, the waterless Ferm-Rite airlocks work very well. They are easy to use and easy to clean and sanitize. I think what will bother alot of users about them is that they are quiet and cannot see bubbling like regular airlocks. Right now I have one on a bulk aging carboy and one on a fermenting carboy. If I listen real close to the fermenting one, I can hear it 'flapping'.
Thanks for allowing me to test these, so far so good.I have no use for the large barrel sized one, so should I send it back to you, or to someone else on this forum to test on a barrel, or to someone on another forum? Just let me know with an address, no problem.