Woah, 3 Hakase pens already. I prefer to keep less pens but good ones only. I have a Nakaya Piccolo Long in EF nib and a Platinum Izumo Yagumonuri on the way. I will not buy a Nakaya again if i buy the Hakase.
I can't buy the Hakase i decided on (QB10A) since it has a smaller axis (diameter i presume, as Yamamoto-san said), has a smaller nib and falls in the DX series whereas the "15/EX" series fits my needs exactly, and takes it to 150,000 yen, and if i need solid gold and not plating it will be 210,000 yen... which is, a lot. This can get really painful if i don't plan this properly.
I guess it will be better to take the 210,000 yen version, i am already throwing so much money at it, might has well throw some more to get solid gold furniture. It's not that as if i will be buying it again.