Etrian Odyssey IV: Legends of the Titan

I'm trying to decide between either pre-ordering a copy of Fire Emblem: Awakening or this game. I've never experienced any entry in either series, so I'm not partial in anyway at all. I need some clarification people!

The demo for this game is now available to download on the 3DS eShop! I was planning to purchase a physical copy of this, so I can receive the artbook and music CD. I just have one question, though. Do 3DS game cartridges still use a battery for the save file, or do they use some type of flash memory?

Did this game ever receive an update for it's lousy 3D effect's?