Yeah, it's way too long and the story is convoluted as fuck. But the characters are great and the setting of Los Angeles in the 70's is so cool that it doesn't matter. You don't know what's going on and neither does doc.
I prefer this one over Licorice Pizza. That's a good hangout movie too, but the characters are way more likable here. The only letdown was the scene where they get pulled over with Martin Short. I didn't want it to end; it would have been nice to see how that night ended.