From the books, magazines, newspaper articles, and discussions in other movies and documentaries I know on the history of The Beach Boys and Brian Wilson, this is accurate, though I agree with others, sort of underwhelming, even if it touches on all the main points.
The Bonus Features are pretty good.
John Cusack and Paul Dano portrayed Brian Wilson (as old and young) excellently.
Paul Giamatti did a great job as the manipulative psychiatrist that held power over Brian for years.

It was alright but nothing special! I never knew Brian Wilson had such trouble!!

Paul Dano (Brian Wilson) didn’t give me a convincing performance. He seemed lost and simple. His cousin was a gothic drag. I appreciate the musical genius that they tried to convey. Interesting to see how his music came about and his background. I think I wanted more of a biopic than a Hollywood reenactment. Still not sure what Brian Wilson’s diagnosis is: Schizophrenia? Autism? Paranoid? Scared of his creepy dad? Too many anti-psychotic drugs? I am confused why we let our musical genius’s, i.e. Elvis, Brian Wilson, Prince, Michael Jackson, etc., be treated by quack doctors. Don’t get that.

The movie is a gem. Life and times of Brian Wilson. Paul Dano could've played Brian Wilson from young to old without any problems but John Cusak did a pretty nice job too. Paul Giamatti as Eugene Landy and Elizabeth Banks as Melinda gave very strong performances.

This is a good film about the chief songwriter for the Beach Boys- Brian Wilson. It follows him at the apex of his abilities as a songwriter, to the period later in his life when he struggled with mental problems. Both Paul Dano and John Cusack give good performances as Wilson.

I've always loved the music of the Beach Boys, but wasn't aware of their personal lives, especially that of Brian Wilson. So heartbreaking, yet successful in spite of it all. You'll never listen to their music the same way again.

This well-meaning, but so-so biopic of head Beach Boy Brian Wilson (Or beach man as he once insisted to his overbearing father.) tries to tell two distinct stories, one about his brilliant work in the 60s, in which he's played by Paul Dano, and one about the woman (Elizabeth Banks) who saves him from his manipulative, malicious shrink (Paul Giamatti). In the this story he's played by John Cusack, who looks nothing like Wilson. There are good moments (especially when Wilson is working) and the acting is good, but it's uneven and tries to cover too much material. I actually would have preferred a straight documentary. For more about Wilson's mental health issues and musical genius, there's Peter Ames Carlin's book "Catch a Wave." God only knows if this movie could've been better.

This was actually the best film of 2015. Paul Dano is especially good.

A compelling, well-acted biopic, though Beach Boys fans, approach with caution: Despite the sunny packaging, this is not a fun celebration of the band's career. Rather, it's a pretty bleak, intense portrayal of the sad and tormented life of Brian Wilson. The music provides some relief - what a thrill to witness the creation of those harmonies - but you pay for it by having to watch Wilson and the group fall apart. Rock history buffs will be intrigued by the story behind the recording of Pet Sounds; fans looking to hum along with all those great Beach Boys songs about summer and surfing and cars would be better off popping in an album.

The three principal actors -- Elizabeth Banks, John Cusack, Paul Dano -- are pretty close to flawless in this Brian Wilson biopic. Paul Giamatti is terrific as always playing the twisted heavy. My major complaint is that the film drifted on for about 20-30 minutes too long. Also, the PET SOUNDS storytelling is compact and cogent, but the Beach Boys narrative thread unravels from there. Still a fantastic movie.