The Hustler, simply because when you're watching the movie, you get the feeling of being right there, at that time, and you can pretty much feel the atmosphere, even more so, sice the pool hall in that movie, "Aimes", which was really known as "Elkers", as it was just off Times Sq, NYC, and also, the pool playing between Paul and Jackie was real, as they were actually gambling for money, when it was being filmed, in which Jackie hustled $200 out of Paul.
Another good thing about The Hustler is, Jackie was a very good player himself, and had been known to gamble regularly in Elkers or another and more upscale room, "Fitz's" (Unsure of the exact name, but it was mentioned before on the Billiards Digest site last year) with Frank Sinatra, Dean Martin, and a few other well known celebrities would hang out in that room and play.
It was also nice to see Willie Mosconi in the movie, as he did set up a few trick shots in the movie, which I think that he played himself, and they're always a treat to watch
TCoM, seemed a bit too over the top, as reguards the gambling and the situations, but at the same time, it was good that they had as many great players there, the late and truely great, Steve "The Miz" Mizerak, Mike Sigel, Howard Vickory, Grady Mathews, Kieth McCready and many others that were in the movie as extras
The Baltimore Bullit, is an all time classic, pretty much all the legendary pool players of that time, were there, and also the fact that it was about the Johnson City fiasco, made it more entertaining, and also with James Coburn as one of the lead characters, I thought that it is generally a great movie
Poolhall Junkies, Good movie, and some good scenes, but like TCoM, a little bit over the top, but still worth watching at anytime
I guess everyone has their likes and dislikes, in this choice, but for me, if I could pick 2, then it would be The Hustler and The Baltimore Bullit

, but if I could only choose one, then it would be The Hustler
Willie