I hesitated in answering this (even though I'm the OP). I did watch this movie on DVD from the library a few months ago. The reason for my hesitation is that I can't really remember... I remembering it being below average for movies in general, but it was a western, which always bumps it up a little bit in my estimation. I must have been tired when I watched it because I don't really remember much beyond that overall impression and a couple of scenes. For example, when Billy the Kid first makes his appearance, they posed it to make him look like he did in the famous tintype. That was kind of cool.
It seems that the film makers tried to weave a fictional story with fictional characters into the true story of the latter part of Billy the Kid's life. I've always liked stories that did that, as long as they stayed close to the truth. I'm afraid that my knowledge of the true story is weak, but I did note that their portrayal of the Kid's death was different than how I've thought it happened. I'm sure that there are other discrepancies too.
My review, such as it is, finds that the movie is OK, but not great. The mere fact that it's a western, though, elevates it somewhat. I'd be very interested to hear what others have to say.
CC Griff