This is an old thread so my post was based on experience with
Axel Schurholz but without any experience with ZYX kinds.
I now own ZYX Airy and, say, know what I am talking about.
The cantilever/stylus construction by ZYX is different in
comparison with all other carts. On the ''nose'' of the (boron)
cantilever one can see an small tube in which the stylus is
fastened. There is obviously no hole in the cantilever in which
a new stylus can be fitted. So the only option is to exchange
the whole cantilever/stylus combo. This retip kind will cost about
$500. The stylus (alone) retip about $200 (180 GBP by Expert
stylus UK). As is mentioned elsewhere stylus alone retip is
the least problematic. But, according to me, not possible by ZYX.