Currently trying to make the same decision between a Kato or Heiji workhorse, and I think I will go Heiji for exactly bk's reasons.. I don't think I'm competent enough to look after Kato's geometry properly right now and my current knives are carbon (What level of reactivity is the Kato comparable to? Blue super? white 2?).
Having said that, for me at least, the Kato has a VERY special appeal. Don't know why but it seems to have a mysterious allure to it.