For once, DLC is a good thing to happen to a game. It's completely worth the price.
It's more missions for the already lengthy campaign in Valkyria Chronicles 2. Same characters, same areas. Then again, the characters were included in the game itself and Sega gave the codes away for free, so no biggie, and it's entertaining playing with only the original Valkyria Chronicles characters.
It's very much worth the price. There are 22 missions, and if you've exhausted the countless missions included in the main game itself, these extra missions are good for more playtime. The Valkyria Chronicles formula doesn't grow old, and all the missions are very, VERY fun. A-rank them all, if you dare.