Only the 2nd Heinlein I’ve read. Not as impressive as Stranger in a Strange Land, but that’s comparing apples and oranges. The book obviously draws heavily on Heinlein’s military training, and does a good job of giving outsiders a peak into that world without being too instructive. My main complaint is the story arch came much later in the book. The initial set up read more like a journal than a story. That’s fine if I know I’m reading a journal, but I prefer to read journals of real people, even if they’re slightly fictionalized. I needed to know the story was going somewhere earlier on. There were a couple interesting philosophical and cultural questions to wrestle with. I’m enjoying the previous juvenile novel, Rocket Ship “Galileo” much more halfway into it.