I would recommend against getting too many calories for too long from something like Soylent. One issue people are missing is Wolf's law: bone grows into stress

I would recommend against getting too many calories for too long from something like Soylent. One issue people are missing is Wolf's law: bone grows into stress. You want strong knees and ankles? Run. If you don't chew you will end up with a glass jaw and no teeth. This is a common problem in the elderly: they start loosing a couple teeth and they're quickly all gone because they modify their eating choices to avoid foods that have become difficult to chew.