Having read the Book of Mormon several times (many more times of First Nephi - many LDS members will relate) I have to say that somehow much was missed in the true spirit of the book. There were a few shining moments, but they still paled in comparison to the genuine book. I would like to say that this was a good movie and recommend it to everyone, but I cannot honestly say this. I was among many that thought it would be a good idea to bring these scriptures to life in movie form, but when I actually saw this rendering I was disturbed. The embellishments distracted from the text too much to be believable and there were things in the text that should have been left in yet were absent.
I am not going to say "Don't watch the movie" because there was a lot of good things in the movie regardless. You have to look beyond the low-budget production and mediocre acting to see what the producers and actors really tried to portray with this movie. I guess the thing that this (or any movie based on scripture) does is that it puts a face to the characters. Whether you thought these characters played their parts well or not is a matter of research and personal taste. No matter who you cast as these characters you are going to find disagreements in this matter. I do have to agree that Lehi was a disappointment as well as some of the other actors. I believe Nephi, Laman and Laban were done well for the most part. You have to remember though that the people who wrote the Book of Mormon were ordinary people, many with extraordinary commissions by nature of their callings (prophets, missionaries, warriors, etc.), not necessarily literary experts - this doesn't even take into account that they were writing in a language that was awkward for them to write because there was limited space on the plates.
Since there are inaccuracies and deviations from the original scripture in this movie, which I (and many other LDS church members) have been distracted by, you must really read the Book of Mormon and rely on that as your sacred scripture rather than this movie. It is certainly good that it draws people to reading the scripture that wouldn't have read it before seeing the movie, but for me after reading, studying and praying about the book I would have to say "read the book with intent to find the truth, but watch the movie for entertainment and enlightenment."