Or Woolpower as they now call themselves.  It's good!  The loop-stitch inside makes the garments extremely warm - so much so that I use a 200 baselayer as a mid layer.

The nylon content doesn't seem to effect the "non stink" properties of the merino either.

One minor point - due to the loose knitting, the fabric pulls very easily, so rapidly starts to look rather "lived in" - this may, or may not bother you! 

The 400/600 garments are very heavy compared to a fleece of equivalent warmth.

I tried a Woolpower 200g zip neck last winter for my skiing holiday in Andorra along with their neck gaiter and luva hat.  Kept me nice and warm all week and also impressed with the wicking qualities and also by the end of the week it still smelled ok.  It has a cosy feel and no itching either which is something I normally suffer from with wool.

Currently good prices at http://www.wslackandsons.co.uk/shop/woolpower/cat_29.html

Wel if it's good enough for Flashman...

Where do Tamarack get their models?!?!