I like to compress my H.264 files in Compressor.
Also, when I create a file as a Master Back Up I like to keep it in its RAW sequence setting which for me is the clips codec. To do this I go to File, Export, QuickTime Movie. Make sure "Make Movie Self-Contained" is checked. Then make sure Settings is set to Current Settings which it should by default. Then it will put it into what ever codec you where editing in and you will not "compress" it into something else. Hope this is of some help and best of luck.
Stephen Smith
Utah Video Productions
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