What is your output being used for? If you are going to DVD, send it to compressor right from the time line and then into DVD Studio and it will look great. If you need to upload to the web compressor has a preset that works well too. If you are making a Blu-ray disc export it as an Apple Prores file and import that into Toast or whatever you use for BD.
Editing online in FCP is the way to go as there is usually no reason to do offline editing since you are not using tape. Just edit and export! Have fun.
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