I've seen some pretty impressive bulls in the southeast corner (they still look out of place to me) but I recall hunting mule bucks several years ago behind Galloway and I saw a bachelor herd of the biggest elk I think I have ever seen. No doubt that both provinces have some big arse elk, but I would agree that B.C. should have the edge due to sheer numbers.
For a bull over 300", BC is #1.If you want a bull over 375", Alberta is the place to hunt right now.