Hearts of Iron, anyone?
With MH you can spend your precious hours with fun especially if you're new to this kind of game. But if you've played Hearts Of Iron series you'll probably get bored after couple of hours. The game is not bat at all but also not great at all neither. While there's a game called Hearts Of Iron 2 (much more detailed and realistic than MH) "Making History: The Calm and the Storm" could only be a preperation for the big daddy, Hearts Of Iron 2.
You should buy this game if you're only new to this genre. MH is a good place to start. With its easy gameplay you can easily understand how nations work, produce, fight and win wars.
Making History lacks of great amounts of details, especially if you're familiar with HoI you'll find this fact disturbing. Nevertheless, this game is a very good try in this kind of strategy level. Maybe they make Making History 2 and that one will be better than Hearts of Iron 2 or even Hearts of Iron 3, who knows?