You could have a look here
Find FOURTH ELEMENT XEROTHERM UNDERSUIT - LARGE on eBay within, Other SCUBA, SCUBA Snorkelling, Sporting Goods (end time 15-Nov-07 22:48:15 GMT)
I have the Arctics and the fourth element technical and it depends on how much you feel the cold
I use the arctics for around now and im always toasty and in the 'hotter' season of Ireland (all one day of it) i use the technical gear
All the best