As to what might be a good mono test drive, Jaws was released a few year ago with the original mono mix intact. Terminator has the original mono as well, but Terminator is a lower budget film that is a bit rough around the edges. Mad Max has the original mono too, but again a low budget flick. I wish I could be more helpful in recommending a good mix. Most films from the 70s, before stereo caught on, haven't had their original mono included, but most classical-Hollywood films from the 50s, 40s and 30s have. I think the DVDs of Robin Hood and Citizen Kane only have the mono, no remixing or anything. It's actually a bit hard to find a really well-preserved mono mix for more recent films, because they usually either remix in 5.1 or present the stereo version instead, thinking no one cares about the mono. It's only in the last five or six years that the practice has started gaining ground, partly in reaction to all the 5.1 remixes (as in the case of Terminator and Jaws). Maybe someone else can recommend something--Taxi Driver or Close Encounters? Star Wars should be the showboat example of mono mixing, but unfortunately it has never been formally released, instead pieced together from second-hand sources by fans. I have a feeling that when the Academy gave the film its sound awards, they were basing it off the mono mix, which not only was the most common but the one considered the best by the filmmakers and therefore more likely for submission.