A good modernization of a classic.
But the best part of FF7 is undoubtedly the story. It's complex and full of twists and you are presented early on with a beast of a primary antagonist, Sephiroth. And then there was the story of Zack.
If you played FF7, you'll know that we see Zack in a few flashbacks and we get to know why he had such an impact on Cloud. (Don't worry, I won't spoil anything here.) However, there were still parts left unclear. Crisis Core helps us get insight on that.
Without saying too much about the story, I can tell you that I was surprised. This game actually had a compelling story that made you want to go on to find out what happens next, even when it gets to the point where you know what's coming (if you've played FF7 that is). The recurring references to the play LOVELESS and other reminders of FF7 (such as 7th Heaven) were nice as well.
The graphics should not even be mentioned. This is a Final Fantasy game, so of course they're going to be near perfect (and by the way, the cutscenes are flawless). One special feature that this game had that I didn't expect was the super-high-end cutscenes whenever a summon came out.
Battling is a mixed bag. To throw in a bit of negativity with this review, I will say that the battles are incredibly easy. Nevertheless Square did a good job at making the battle system unique, even if it was kind of a random system. Numbers and faces keep spinning in the upper left corner of your screen, and certain combinations give you temporary boosts during battle (even invincibility!) However, this system is also the only way to level up, so in some cases, it can break the game.
The missions are fairly simple. You're basically given a task to do and warped to some generic field or building where you must find an item or destroy everything in sight. They're good to do if you want to gain new magic or items or even summons. You can even do them to level up before your real missions.
Overall, if you're a fan of Final Fantasy VII and you own a PSP, it would be worth your while to check this game out. It's especially nostalgic for those who want to see the old Nibelheim scenes revisited in more modern graphics. It's not one of the greatest games you'll find, but it's nothing to scoff at either.