In fact, here many people are talking about the way how to import Panasonic P2 MXF files into Final Cut Pro for editing without problems. Well, don’t blame to the Final Cut, the “Import from Camera…” option works just like “Log and Transfer”. The thing is, even FCP X does not work with the Panasonic P2 MXF codec. As far as i know, to solve those problems, the most important piece of the equation is that transcoding Panasonic P2 Card MXF files to a FCP's supported video format, like Apple ProRes (422).
If you want to edit Panasonic HPX-170 P2 MXF files in FCP(x), you'd better transcode P2 MXF to Apple ProRes MOV format first for smooth editing with Final Cut Pro.