I've been wondering that myself. At least for Portable 2 I heard that the only difference between Asia and Japan region is the manual and the price. Asia has a manual that is in english and is cheaper (for some reason) while Japan does not. I don't know if that's true beause I could not get my hands on the Asia region (they're also rarer for some reason).
Random: I could get something as low as 10% on my upcoming chem final, and I would still bump my grade up from a B+ to an A-. lol
Random: I could get something as low as 10% on my upcoming chem final, and I would still bump my grade up from a B+ to an A-. lol