Well think about it, m2k can pretty much bring the full potential of fox out. Armada, while not being able to do the same, is a lot closer than any other pit player, when it comes to reaching the full potential of the character. m2k has some experience in the MU and armada has the experience as well. I realize the level of experience does differ, but for Armada to preform so convincingly against m2ks fox, that has to say something about the MU.
Having chain grabs, gimps, reliable kill moves/setups, good normals(i think?), (etc) plus what was done in several matches at apex 2014, should show all the foxes out there, this MU isn't completely in our favor or at least not free, if anything, it could be inching in pits favor.
imo this MU should be 50:50 at the least
It could be like lordling said 55:45 pits favor
Then again, m2k and armada are so above us... meh