MUC for ease. ZRH is a little odd in that one often has to reclear security for a connection with intra-Europe gates in sections.

But the chocolate purchasing opportunities are good at ZRH Then again, if one has sufficient time the gelato purchasing opportunity is good at MUC in the central zone.

But I will always vote for MUC when given the choice of ZRH/FRA/MUC. Has nothing at all to do with username.