I'm sure this has been covered before but I want to get this right...

I'm putting together a ranma 1/2 information page (I know it's been done but
it's just giving me something to do <g>) and wanted to get this straight.
Spelling. The way I see it the commercial spelling of most names in Ranma
seems to be just 'o' for names like Ryoga, Ukyo and Kuno while a lot of
people here seem to prefer Ryouga, Ukyou and Kunou. Wanting to get to the
heart of it I asked a Japanese friend who said that she spelled the names
like Viz does but uses '' if she wants to be more accurate. If this has
been argued before (and I'm sure it has) can someone just point me out to
the decided-upon spelling?

Vigil