I currently has luma 8.1 and b9s. I have bbm replacing health. My questions: 1)I would like to system format it for some reason, is it okay to do this?what will I lose?Will I lose bbm/luma 8.1/health bbm? 2)I want to upgrade to 128gb msd(currently using 8gb). I heard it is problematic with bbm. But my only cia installer is bbm for now(health). What should I do and which Cia installer do you recommend that work with 128gb msd? 3) currently I am on 11.4. I would like to use GW again if possible. What should be done in order to use it again? 4.This is a japanese system. Do you recommend changing the region to US or should I leave it be? I only want to be able to play all region game with all their dlc. Thanks!