Flawed multi-player design prevents it from being what it should.
The first thing anyone needs to know about this game is that it's essentially nothing but multiplayer. There's supposed "Story" missions that are really just shooting things with immensely vague and pointless dialogue between characters you can't even see. They exist solely as subtitles in your mind.
But who cares, that's not why I bought Armored Core V. I bought it because I wanted to make a fruity-colored death machine with four legs and no visible head. So that's exactly what I did. I named it Fluffykins. The customization of your AC is immense, and I mean immense. Far from simply letting you adjust what weapons and parts your AC is using, you are also capable of designing your own emblems and decals that you can apply anywhere onto your AC. You can also choose different color schemes for every single individual piece of your AC.
So after Fluffykins was combat-ready I eagerly slapped my favorite Pulse Cannons on and wondered what I could do next. I ended up joining a "Free Battle" room with my Team and we spent the next few hours fighting each other and any random people that joined the room. Unfortunately "Free Battle" offers no rewards and no incentive to do it apart from just wanting to fight. You don't really care though, because this is when the game is actually really fun: when you're capable of tweaking and testing your AC and then seeing the results in combat with other player ACs.
Unfortunately, actually using those ACs in glorious battles with other players is hampered by some seriously flawed design choices regarding the multiplayer component of the game. Make no mistake, the combat itself is riotous fun, especially in large battles with many ACs on the field. It's just that actually getting together with people and fighting them usually requires a near miracle.
In order to even really play the game, you have to be on a Team. You can't even buy parts from the Shop without being on a Team. This isn't too obnoxious because you can always create your own one-man army. However, the main point of the game is Teams fighting over territories on a persistent world map, so solo teams really don't have much appeal to them. You can hire random players as mercenaries to field your squad but it just isn't nearly as fun when you don't share any team spirit with your fellow AC pilots.
To cap it all, the main attraction, Invasion and Stronghold missions, rarely ever successfully work. Most of the time you simply join an empty lobby with no opposing team to fight and the game doesn't let you start without one so you end up just wasting time. It's like the game requires a defending team to just be sitting patiently in a Stronghold mission on the off-chance that someone might Invade them. Only then does the mission actually work. It's a terrible idea that relies far too much on players finding each other by chance. If Stronghold and Invade missions worked reliably and the Conquest map was an active, bloody war of ACs duking it out for world domination, this game would be immense fun. It doesn't help that you lose a massive amount of Team Points after an Invasion mission, win or lose. This means you're forced to grind them back before you're even allowed to attempt another Invasion mission, which probably won't work anyway.
And if that wasn't enough, actual game glitches and server disconnects make their appearances too. All sorts of odd things can also happen if you do manage to successfully find a game. The glaring message "MEMBER DESTROYED" once appeared on my screen over and over for the entire round. If it was to be believed, I apparently lost around eighty of my four team members. The game simply crashes sometimes too and freezes on loading screens, forcing you to restart. It also sometimes loses sync and you're teammates will ask you what you're shooting at when you're firing at an enemy AC. Confusedly, you'll tell them you're firing at the enemy and they'll tell you that you're firing at nothing on their screen.
BOTTOM LINE: 7/10
All in all, the fun of Free Battles and the rare Invasion/Stronghold mission cannot be denied. The shop is a little thin on parts right now, but hopefully more will be added in the future. Tinkering with your AC is enormous fun and you can truly personalize to be your own. The only thing really missing from this game is solid, dependable, addictive multiplayer. All too often we're left wondering what we should do in AC5. The answer should be obvious: we want to blow other people up.