Mmm, I was pretty addicted at one point, but now I just buy them here and there as a treat. They are pretty expensive and it's easy to overdo them.
But a few months ago, the best brand (G.T.'s Kombucha) got pulled from the shelves in Illinois for having too much alcohol in it, I think, and now it hasn't been available. I miss it.... the other brands just don't compare.