I don't see you citing anything. Also, I never confirmed or denied their "claims", I simply stated others have tried it and it's not going to "kill" you or anything.
Your original post's attitude seemed to imply it was almost risky to consume this as it's made by people aged "20 or so". Not only do I find your age discrimination shocking, I also take issue with your sarcastic tone.
If you want evidence, I can think of two sources:
[1] http://discourse.soylent.me/ -- Plenty of people on the discussion boards
[2] http://www.youtube.com/watch?v=I8WpksPED_Q -- Week long study
