This film is so bad, I broke out laughing during some of the "serious scenes". Its a good cast overall, but Kiefer is badly miscast. He has come into his own as a good actor in darker roles, but he is awful as the happy-go-lucky naive hippy.
The screenplay is to blame. Its cliche from beginning to end, and really fails to capture the vibe of America in 1969. The Soundtrack is essentially the greatest hits of the late 60's, which adds to the cliche.
In the end, it comes off as 1969 as imagined by the 80's generation and is inauthentic to the core.