Clayton MacKnight April 10, 2014, 11:38 pm. I don’t think it really matters. I almost always use just the hiragana setting. Sometimes, you have to use full-width alphanumeric for poorly programmed web forms though (like if you have to register for online banking in Japan or something like that). Reply Link. Peter May 6, 2014, 12:31 pm. I have the windows IME set up on two machines, using it.