The Godfather II does a great deal right, and if you're a fan of the open world genre, you'll probably enjoy the hell out of it. If you've never played or enjoyed an open world game, The Escapist would probably still recommend you try The Godfather II. There are certainly worse introductions to the genre. GTA IV, they're looking at you.
Recommendation: Buy it. Just remember, it's not personal. It's only business. Also, don't ever ask me about my business, Kay. And leave the gun, but take the cannolli.