In case you weren't born yet, Merczrox probably means he likes
the previous Mercedes Benz O405s. I know the Citaros are also from
MB, but that doesn't mean he has to like all Mercedes buses.
Just like you like Lexus LFA, doesn't mean you have to like all
the other Lexus models right? (I know this example is weird, but to
the others you get my point).
If I remember correctly he had created this username somewhere
in 2008, simply because he liked those SBST 0405s when they were
still on the roads.
Somehow I don't understand this clone user SMB228X... He likes
the Citaro so much and instead he use a SMRT MAN rego as his
username.