The influence of the polymer network on the dynamic switching behaviour of polymer-stabilised pi-cell devices is investigated in detail. The stabilisation technique is shown experimentally to increase the relaxation and switch-on times of the device when small concentrations of polymer are used. Modelling of the device indicates that this is due to the polymer network suppressing the fluid flow during switching. A comparison between a conventional pi-cell and a polymer-stabilised device with the same switchable range of transmission indicates that addition of the polymer network increases the relaxation time by 1.7 times.