Here's a summary of all the information presented in this thread, for your convenience. All credit is given to the awesome users that responded. Can .CIA be converted back to .3DS? If the .CIA file is not encrypted, yes. If a .3DS game is run (and saves), will a .CIA version detect and use that save? No, unless the game is a card2 game (for example, Pokemon or AC:NL), in which the save file can be extracted with SaveDataFiler and re-injected. Can a .CIA file be run directly off a Gateway card, or must it always be installed to internal SD? No. .CIA files are entirely made for being installed to the NAND of the 3DS (or the emuNAND). Aside from avoiding using the Gateway game browser, what advantages does .CIA have over .3DS? Certain homebrew can be used with installed .CIA titles. Also convenience, such as having your favorite games easily accessed on the 3DS home screen. Current Questions: - Are there certain games that cannot be run in .cia format, but can be run in .3ds format? - Are there any performance differences? - I've heard of certain games freezing and locking up. Is this any less or more likely with a .cia format? - Is it particularly difficult to convert a .3ds file to .cia? Can any game be converted? - Is there actually a 32gb internal storage cap for the 3DS as Orcastraw stated? And a major question: - In your opinion, with the upcoming Gateway 3DS update, is installing .cia files recommended (given that these will not be installed using an emuNAND, but rather to the actual 3DS console itself)? Couldn't Nintendo cross-check the installed games versus the actual purchased e-ship titles?