This movie screams '70s art film. Part of that makes it a great watch, while the other part of it gets a bit annoying. I kind of like the concept of not knowing all the details of his alien heritage until we get to know him better. He just kind of starts where he fell, and we watch his plans unfold.
The most interesting aspect (and the reason I own this) is watching David Bowie in his first big acting role. Quite frankly, he shows his skill right from the start. This isn't an easy, normal role either. Perhaps that's why he took it, because he was so out there at the time. Down the road he just kept being great in movies, especially Zoolander of course.
Anyway, I'd recommend this if you're in the right mood for it. Certainly worth checking out, even if you're just interested in it as a look at the production.