This game is extremely enjoyable. I loved every second of play. While it has its flaws, it is very well done.
Okay, let's check out the gameplay. In campaign mode, you go through a series of missions. Harder missions get you more mission points. You also get to have multiple Mobile Suits to choose from, some built for space. Oh, did I mention that you can play for either side? That's right, kids, you can fight for the honor of the federation, or rebel as a Zeon warrior. In arcade mode, well, it's just basically a linear and short version of campaign mode. However, you can unlock Mobile Suits for the awesome... VS. MODE! You can play together with a friend or against him, or just face the computer. Combine that with the ability to choose environments and mobile suits, and you've got hours of fun with your friends.
In terms of story, well, it has the story of the original Gundam anime series built into campaign mode. So, basically, fans of the series...