According to the ESRB, this game contains: Fantasy Violence
Parents don't have anything to worry about. The only violence in the game consists of robots shooting each other with guns and rockets. There is no blood or gore, and even when the robots are defeated they only "shutdown" in a puff of smoke and some noise. There is no questionable language, and no sexual situations. It's an extremely difficult game for inexperienced players, and an unfriendly one, but it won't be corrupting any youth.
Action gamers will want to let this one pass by. While it's true that the game revolves around arena style battles, each match plays out almost exactly the same way and without a love of robots and machinery, there is no reason at all to play this.
Armored Core fans will most likely be disappointed in what this game has to offer. There are no missions, no store, no money, and it's been reported that by carrying over and using old data, it activates a programming glitch which prevents players from collecting all of the available parts. The arena can be finished in one long day, and the training missions are so difficult and dull, only the hardest of the hardcore will find patience to sit through them.
Deaf and Hard of Hearing gamers are at a slight disadvantage since the sound of weapons firing can sometimes be the difference between success or failure. This particular aspect of gameplay is not reflected visually onscreen until you've eaten the missile, but otherwise the game is fine. All voiceovers are accompanied with text and there's no real story to speak of, so there's nothing to miss out on there.