I don't have much of a thing against Ubisoft because I play most of their games on console, thereby avoiding the DRM for Hades. Though I do resent them for trying to turn Assassin's Creed into an annual money-grabber.
EA are just being true dicks. I truly cannot see how they can mess around with their customers so much without actually having a dicking about department. Can't really boycott them though because they seem to publish half the games out there.
Now, I don't play many Activision games. I never got into CoD, only having bought World at War for the zombie bit. I never got into WoW either, my soul having already been taken by Runescape (I've got it back now).
So, it's a mash-up between Ubisoft and Activision. I'm going with Activison.
Why, I hear you ask. Well, though I haven't had much of a quarrel with even with them, Ubioft hasen't done anything nice for me, while Activision has. And what has Activision done for me?
Simple. By typing in the barcode from my age-old copy of Warcraft 3 and it's expansion pack, it let me redownload them. Those games are a part of my middling-childhood. Very few companies let me do that, and I applaud Activision for it.