YMMV / Armored Core

• Complacent Gaming Syndrome:
  • For those who enjoys the benefit of Human Plus in their playthrough, most people tend to stop at the fourth surgery to gain most of it's useful perks such as permanent radar and no kneeling required to fire certain back weapons. Any other upgrades is just making the game too easy.
  • Most players will side with Chrome despite being the hardest route of the two, simply for better mission variety and the secrets you obtain, like the best booster unit and the MOONLIGHT Blade. In contrast, the secret parts you get from siding with Murakumo are often overshadowed by better options or just impractical to use, with only the best generator being an exception, and the mission where you can get the KARASAWA Rifle is a mandatory mission that you must play to progress regardless of which corporations you're siding with.
  • The second-tier machine gun. It's ammo is not as plentiful as the next machine gun and the firerate is also slower, but each shot is somewhat stronger and costs less, so you'll likely stick to it for the rest of the game. Ditto with the third-tier energy sword, since it's pretty lightweight while also strong enough before you unlock the MOONLIGHT Blade.
• That One Level: The last mission of the game is infamous among players for including a lengthy and difficult platforming section, which the controls of the game are not well suited for. Getting up to the top is already difficult and time-consuming enough, but when you do get up, you have to contend with not one, but two Nine-Balls, the most powerful AC in the game with incredible firepower and agility, one of which would already be incredibly difficult to defeat. Defeating them isn't mandatory and you can just rush past them to the goal, but this isn't easy to do either and they can catch up to you if you aren't fast enough.
• Scrappy Mechanic:
  • Once you roll the credits and unlocked the replayable missions, any Human Plus cutscene and triggers is basically disabled, essentially locking that savegame from gaining any (other) Human Plus upgrades no matter how much debts you sunk yourself into. If you completed the game without Human Plus upgrades and wanted to get one in that save, think again. You better start a fresh save instead. You also can't reobtain new Human Plus upgrades if you import your save to the Project Phantasma and/or Master of Arena, so you'll be stuck with whatever how many upgrades you obtain (or in non-Human Plus run, none at all) and have to obtain everything you need before importing them into the next game.