From what I can tel the AI performance is much better. Just got my first chance to test multiplayer though and I am not impressed. I was trying to purchase just 1 troop in a town to go rescue my heroes and it just kept on crashing. Another thing I noticed is that the game doesn't like multiple network ports. I had to shutdown my external interface in order to play with my Girlfriend over the airport connection. It's back to Heroes III Complete for me. It has the same network port issue, but at least it doesn't crash and it's playable.