I had been using MPlayerX for years and never really liked it. It always took a full minute to open even the smallest video file. It often froze on larger files. But when I found that the latest version from the developer at codeplex, the same version offered on this site (which has now been replaced by the safe version from sourceforge), contained 16 out of 45 malware positives at Virustotal, that was it. I looked for and found a much better alternative called 'mpv', which is based on 'mplayer', but has many more features. It loads immediately, unlike MPlayerX, which takes at least a minute to load a video. It handles playlists, or you can select a bunch of videos and open them all, like a playlist, with 'CMD-o'. It has many more features than command-line 'mplayer', and is an app, so you can open files from Finder in it. It is highly configurable if you don't mind reading the docs and editing a config file. After experiencing 'mpv' I will never go back to MPlayerX.
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