I was a bit disappointed with Empire I, which was too simplistic, too much like RISK, too unreliable, and not all the rules made sense as written.
However, Conquest of the Empire II is awesome, and makes the game well worth the purchase! Its got the perfect balance of strategy, empire-building, and military action. It offers various possible victory strategies, and a lot of variants. We've only played one game, but I'm willing to bet dollars to doughnuts that, like my favourite wargame History of the World, no two games of Empire will end up playing out the same way.
RPGPundit