The perpetuelle certainly is close to the calendrier, but --with one caveat-- if I didn't already own a calendrier and were buying one or the other, I'd opt for the perpetuelle. Journe has been very fair in its pricing differential for the added complication and the limitation here means something more than the dial variations we have seen so far on other models. I must confess, though, that I don't understand the choice of titanium for this watch. The design is not a sporty one to my eyes, and, while I think that the use of non-precious metal on the limited chronometre souverains made sense aesthetically (and it of course makes sense operationally for those folks (not this writer) who can afford a Sonnerie), I don't understand its selection here.