Quite liked it. As in "The Left Hand of Darkness", an envoy of sorts is sent from one culture to another, but here, both these cultures are discussed, and neither is as alien as the one in Darkness. A kind of anarchist society meets a kind of capitalist society, and both share a common past.
Interesting to note are the alien concepts of physics that are a main plot point; they sound more thought-out than Star Trek technobabble, but still aren't meant to be taken quite seriously. Simply alien/weird. I'm almost as sure that the religious/philosophical (anarchist) theories debated aren't meant to be scrutinized too closely either, that would be Hubbard territory. But they're given a lot of pages, a smidgeon too, I thought.
Well-written, interesting worlds.