Necropolis or Castle (Which one is stronger?)

Personally, I almost always play a random XL map with a Dungeon, no water, the strongest guards, 5-7 computer opponents, and impossible difficulty, and I usually finish it in under 130 days, without rushing events, but developing gradually. I've seen 800-1000 spell points a couple of times (on my own hero). In general, the computer opponents play foolishly, although they have a lot of units and often try to take a town without any guards.