I am using Plan-G with Xplane 10 and love both.  I am starting to put more time into creating flight plans and I save as an .fms file and upload to the xplane FMC and Plan-G.  One big wish I have is having the ability to just upload/create the flight plan on either the FMC or Plan-G and have it sync to the other; and subsequent flight plan changes automatically synced between the two.  I don't believe this is possible now, but if I am missing something and this is possible please comment.