And there's a new version of Soylent on the market and in my pantry. This new version is a bit sweeter than 1.5 and has a distinctive smoothness to it. 1.5 was grainier, and while some people like the textural element, I much prefer the smoothness of 1.6. It also mixes better and is easier to clean out of shaker cups, which I love.
Check out the official Soylent blog on 1.6 for more info.