It's not all that bad! I have a Japanese boyfriend and he's very sweet and kind. :) I lived in Japan for a year and thats kind of the "feel" I got from dating there. So while that advice isn't good for everyone, there is a vain side to dating japanese men sometimes. However (and this isnt exactly good either) just being a foreigner in Japan makes you pretty so it kind of works for the vain thing..?
Anyways as a whole people are nice and the culture is wonderful!