I've been on this Ars Magica trip lately. The first edition I ever saw was the 2nd and it opened spaces. The later ones where massive turn offs. The 2nd ed rekindled my curiosity as I read it again lately.
Having gotten and read the supplement "Order of Hermes", even though it's not one of the later humongous and dense ones, I once more felt it was a slog.
It's a game with so much potentail that drowns in bummers as it gets detailed.