The most impressive thing about this film is that it might actually be the most 5 out of 10 film ever made. Firstly, I'll give an overview of the good stuff. The costumes and sets are superbly executed. The production team did a fantastic job of transporting me back to 1970's LA. The acting is also very good. Alana Haim and Cooper Hoffman both put in excellent turns as the two leads. While, the cameos by Sean Penn, Tom Waits, and Bradley Cooper are probably the most entertaining parts of the movies.
Now the bad. Firstly, the dialogue is baffling. The chitchat in the opening scene stinks. The only explanation I could possible come up with was that they'd invited George Lucas to come in to punch it up. Secondly, the script is just bizzare. The writers throw so many balls into the air that never have any payoff. Firstly, Gary (Cooper Hoffman) is a child actor. Then, he owns a water bed company. Then Alana (Alana Haim) wants to be an actor. Then Gary owns a pinball arcade. Then Alana works as a volunteer on a political campaign.
The movie just doesn't seem to know what story it is trying to tell. On its cover it's a love story, but neither of the main characters seem to be that invested in each other in a romantic sense. Alana has something of a coming of age story, but I don't really buy that she's learnt anything at the end. It's also not a comedy, there aren't many funny moments.
Finally, at 133 minutes, the movie is way too long. I found myself looking at my watch on multiple occasions.
Anyway, if you want to watch a visually interesting movie. This is not a terrible way to spend 2 hours. But, don't expect much else. There isn't much to like about the main characters and the plot is trash.