I found that the single player was faster because you can sometimes do multiple NPC quests at the same time. If your party is loaded up with your own generated characters then you only have room for one or two NPCs. A lot of the NPC quests have lag times between developments and if you can coordinate them together the game goes by faster. For me at least. However, if you don't do any NPC quests then the game should go by faster in Multi player.
|