One thing I've noticed with kombucha, kefir & any probiotic is that once you stop taking them, the effect finishes. I found some science on this here, and it's apparently true: exogenous bacteria don't colonise the human gut. They'll hang around and do good for as long as you take them, but that's it. So I wonder if there is some way of getting exogenous bacteria to colonise the gut - i.e. stay there? (Weak character that I am, I can't overcome the gross-out factor with fecal transfer, assuming that works.) This is important IMO as those good bacteria do a million good things down there, including assist B12 absorption, & reduce leaky gut. And I'm not sure I want to have to depend on supplementing probiotics every day for the rest of my life.