I'm not impressed by solylent at all. It's not really a whole foods type product. The only whole food ingredient in it that i can tell, is oat flour. Oats are a great food, provided they are well soaked and then well cooked. Why, because they contain such a high level of phytates which are anti nutrients that bind to minerals and proteins making them unusable by the body. It seems that traditional cultures that used oats somehow knew this, because almost all of them would both soak and cook the oats for a long time, the combo of which gets rid of the phytates. (another high phytate food is soybeans, and traditional cultures would often ferment same, which is another way to get rid of these anti-nutrients).
I'm guessing they are just using ground up raw oat flour, which is not going to get cooked. No bueno.
Then, most of the nutrients added, especially the vitamins are the typical, cheap, and less bioavailable and more synthetic types. Some of the minerals might be in a sense "natural", but take the calcium they use–calcium carbonate–it's essentially chalk and not one of the more bioavailable forms of calcium.
While it's a bit expensive, something like Garden of Life Raw Meal will be MUCH better for the body. I think they do add some extra nutrients, but these are food sourced, and the main ingredients themselves are highly nutritious and highly bioavailable.