I read this back in my late teens I think, and enjoyed it enough to re-read at least once over the years. Not award-winning literature to be sure, but entertaining and thought-provoking. There's a decent movie adaptation waiting there for the right creative team.
As for Ingo Swann himself, well — on the psychic front, seems mostly a clever, creative magician/theatrical con man who _might_ have some psychic abilities, assuming such things are even real. I remain open to the possibility of conclusive, scientifically verifiable/reproducible proof of psychic phenomena, if or when such proof ever appears. :)