At the end of the screener we attended the woman leaving the theatre
with her friend used the word "torturous" and she wasn't far wrong.
It's not a terrible film, it's just not very good. The songs
are bland, the script doesn't help and the characters' actions
largely don't ring true or make sense.
The film does have it's moments and the first half-hour makes promises that the film then fails to deliver on. The opening set pieces, the costumes and the drama of the talent contest creates expectations of a 'Ray'-like mix of drama, music and song with great costumes. From here it's downhill with a few bright spots: Eddie Murphy's great, mugging it up for the backrow, never less than imperious; Beyonce's performance suggests she might excel at something that pushed her a bit harder and no one's musical talent is in doubt, they've just been asked to perform some pretty plain songs.
UPDATE: My wife disagrees. She says it is a Terrible film.