If I remember right, there was a gamma shift out of FCP as well, and the fix was (with QT 7) to check a preference in QT to “Match FCP gamma adjustments.” QTX did not offer this fix.
As for the multi-cam, I stick with FCP 7, not wanting to mess with FCPX and frustrated with the inability to collapse multi-clips in Premiere or get any usable EDL out (Premiere won’t reference the source code) to conform. If you don’t need that functionality, the multicam tools in Premiere are workable.