It's good, other than suspending disbelief in a few instances with Maggie & Jeff. Collin Farrel was particularly good. Ryan Bingham is responsible for some of the music. The movie is dedicated to Stephen Bruton, the legendary Texas musician, and a lifelong friend of Burnett's, wrote or co-wrote most of the original music performed by Bridges and Ryan Bingham. Collin Farrel is also actually singing here. The best song is "Fallin' & Flying" which shows up twice, once with Farrel and Bridges, once just Bridges.
Certainly agree with you on the disbelief on Maggie/Jeff. Of course, it's hard to imagine after a while why anyone would want to associate with the Bridges character given the affects of his alcoholism on him.