I thought the chemistry among the three leads - Gordon McRae as Buddy De Sylva, Dan Dailey as Ray Henderson, and Ernest Borgnine as Lew Brown - was absolutely perfect even if not necessarily true. Probably the hardest thing to take at first is the excessively caustic nature of Borgnine's portrayal of Lew Brown until you get to know a little more about Lew, his background, and his friends and then things begin to make sense. There's a good contrast of personalities here - De Sylva civilized but selfish versus the street-wise loud and rude Brown who'd put it all on the line for a friend. Henderson's gentle family man play-for-keeps style versus De Sylva's flavor-of-the-month attitude towards women. I don't know if any of this was true, but as cinema I liked it.
Knowing something about the early talkie musicals and the composers behind them, some things did bother me. At one point the film has the three going out to Hollywood to work on the 1929 early talkie musical "Sunnyside Up". This was largely a homespun little film in the tradition of the early Fox musicals with even a harpsichord number included. Instead, what we see on the set is an elaborate fan-dance like number with a man in a tuxedo singing "If I Had a Talking Picture of You" accompanied by dancing girls with long red boas. This is not how I remember Charles Farrell singing this one. In fact, if there is one big complaint I have is that the songs are pure 20's but the choreography and tempo of the numbers are like something out of an MGM musical ballet with Gene Kelly that would have been popular at the time of the film's release - 1956.
The key to enjoying this film is to focus on the beautiful music, good performances, and the pleasant nature of the story. Do that and I think you'll like it. I don't think this was ever intended to be a serious biopic.