I'm new to the Armored Core series, relatively speaking. I found out about it when the PS2 launched, with Armored Core 2. Completely unlike any other mech game, it did away with lumbering bipedal tanks with giant howitzer cannons on their backs, and replaced them with slick humanoid like robots with afterburners (though if you still liked that old-school Mechwarrior feel, you could certainly build one, too!).
Almost a decade later, I'm playing the addendum to Armored Core 4, now curiously named "For Answer". First of all, the game is BEE-YOO-TEE-FULL! Customization is unlike anything it was before as individual pieces seem to be more than just a graphical change. Their animations are different, as well as their coloring schemes, which of course, you can still edit to your hearts content. Multiple unique weapons allow you to create a NEXT that is suited just for you. Any concept of "the best" anything is out the window, as every item has a purpose now, allowing you to finely tweak your bipedal battle tank. And now, they've added Assault Armor, which can replace your overed booster. By sacrificing a bit of booster efficiency and power, you can turn your NEXT into a bomb, detonating anything around you and destroying all local Primal Armor of other NEXTs. You'll still regenerate your PA, but at a much more reduced rate. Ultimately, it solves the old dilemma of "Too many enemies, not enough bullets" that made us Core players very stingy with our bullets.
The game suffers from occasional slow down when there are too many missiles, or on screen projectiles, but it's something I can tolerate these days. I come from the Gradius, Super C, Shadow of the Ninja era after all. All in all, if you love robots you should get this game. If you love Armored Core, you should definitely check out this brilliant installment into an already stellar library.
Simulation/Giant Robot Simulation