dont under estimate mjpg. most video cards used that codec to capture back in the days
mjpg is normally no used in a video context. it might be useful for certain materials, or when you later want to extract single frames in order to make picture files out of them, but while editing it would be a strange codec.
yet there is one application where it can make sense, and that is when you normally would like to work with uncompressed material but you dont have the CPU, HD speed, or RAM speed to do so, because you want to play a bigger sized film or because you need 2 or 4 tracks to be played in realtime.
i havent compared it, but using motion jpg with 100% quality while editing might be a good alternative to the animation codec, which tends to create evil artefacts (which you dont see instantly but only later after further editing.)
as final codec, mjpeg ist probably bullshit.
but to be honest, as almost all compression codecs present and available for OS9 today are pretty outdated, you can no longer recommend anyone to use one of them to create a final media file anyway.
the most intresting formats which the average user needs are mp4 and/or H264, where the latter soon will be outdated, too, which will mean that compressing "finals" should no longer be done on a G4 but only on OSX 10.6 and higher.
i am neither a playkid nor an "industry pro", i personally work only with uncompressed video (which is in my case, with PAl, SECAM, 400x800 and 450*900 not much bigger than DV25 would be), and compression happens in OSX, usually i always made a default quicktime container with H264, after i noticed that can cause trouble with later OSX versions, i now make .mp4 files using H264.
to come back to the topic: final cut pro is a terrible program.
