Strictly speaking, the content of Update 1.5 is the same regardless of whether you download it from the eShop or install it via a CIA file. However, the CIA format offers specific advantages for certain users:
Obtain the file from a trusted source like the hShop. Copy the CIA file to your SD card. Open the FBI app on your 3DS. Navigate to the file and select "Install and delete CIA" . pokemon x update 15 cia better
If you are using a standard retail 3DS, you can still download the update by following the Official Nintendo Support guide and scanning the provided QR code. For users with CFW: Strictly speaking, the content of Update 1
It enhanced detection for unauthorized data manipulation in competitive play. Open the FBI app on your 3DS
For players using emulators like Citra, a CIA file is the required format to manually "install" the update into the emulator environment.
It ensures protection against the infamous "Lumiose City glitch," which could previously corrupt save files if the game was saved in the outer ring of the city.