I called Federal with the same question about four years ago.
They said there was no difference except the degree of QC the Match primers undergo. What they meant by that, I haven't a clue. They did, when specifically asked, tell me that the primer compound is exactly the same between the two.
I've been told (not by Federal) that the cup thickness is different, but I've never checked that myself. I use the two primers interchangeably, and don't modify my recipes on account of it. I can't tell a difference between the two over the chrono or on target.
Mike