Estel's reply has really piqued my interest! so i've created a swap partition on my microsd and set both the default swap and the microsd swap locations as having the same priority to spread load out evenly.

i'll monitor these over the next couple of days.

Estel - do you mean using iostat to monitor total blocks written to the microsd swap partition? if so, this should be quite easy to script and have it run via alarmed every 24 hours.