It doesn't play most files without codecs, which you have to download piecemeal, and which come bloated with players you don't want and shouldn't need. Even then it's hit and miss - I've been burning DVDs to mpg, to avoid compression/loss of quality, and while these start up and run along ok, the application freezes if you attempt to skip forward. Other (avi) files play squashed and indecipherably, though these same files work fine on other players. I've been searching for answers through Google, and everyone says to use VLC, which I've downloaded. The problem is VLC won't allow multiple instances, so you can only open one video at a time - this is configurable on Windows, but not on a Mac, because the OS won't run the same application more than once. So VLC is unsatisfactory (because of the OS), and QT won't play most files properly. Windows is rubbish in all sorts of ways, but Apple always shows off about how it "just works", and clearly if I have to hunt down bloated codecs, which don't fully work, and if I can't do something as simple as running multiple video files simultaneously, then this claim is somewhat suspect. It's really disappointing when Apple screws up like this - and this has been the situation for years, so I guess they don't think it's a problem (should I stop using my computer like this?). Please someone tell me I'm wrong, and that I'm missing something simple.