I've found that converting mpeg-2 into DV, especially into final cut pro via ffmpegx, really looks bad, quality drops severely, converting into quicktime movie is better but not by much, there is a cropping and quality issue, any suggestion would appreciated,
also I've found that PC files will often end in .MOD this can be changed on a Mac to the suffix .mv2 then, using the freeware ffmpegx you can go into fcp.
thanks for the DVDxDV suggestion, I'm off to give it a try