Cool, but what I really need to know is if two characters next to each other make a square, such that I can have CJK characters in the same line and not muck up the formatting.
:set guifont=mononoki:h11:cANSI
:set guifontwide=MS_Mincho:h11:cANSI
Basically this mixture of two fonts, one for one-space-characters and another for the Unicode two-spacers, is up to your editor to get right.
I tried increasing the size of the guifontwide. No matter what size I pick, the alignment is correct; for excessively large sizes of the wide font relative to the regular one, the kanji just start to get jammed together. Basically you have to increase their sizes together to avoid the cramping.