The pegs for the PG Zeta is not exactly tough enough to hold the legs in Wave Rider mode AND take occassional abuse. One of the pegs on mine is showing white stress mark. They should have cast these pegs as diecast parts instead. Other than that, everything locks into position rather nicely.
The polycaps aren't too great at maintaining poses in MS mode, however, due to the weight of the plastic vs. the strength of the polycaps.