Is Zeiss vignetting superior to Canon vignetting?

Vignetting is easy to correct in post, but the 'cost' is some extra noise at the edges where the exposure is pushed. OTOH, if you like the effect it's also easy to add in post, with no 'cost' (and I sometimes do). So on the whole, I'd prefer less vignetting - but it's not such a big deal either way.