In reply to MtnGeekUK: It seems everyone is making a competitor these days. I just got the Rab MeCo hoody for reviewing for example - from the harsh testing ground of trying it on in the UPS depot car park after going to pick up the parcel, I can say it's lovely, although RAB are making one in polartec fleecey base layer stuff as well which will be closer to the R1 than the MeCo merino.
If you have a friend in Canada, this is the cheap option
http://www.mec.ca/product/5026-604/mec-t3-hoodie-mens/ I've had one for years - its great, but the material is a bit lighter than the R1. I've had a non-hooded R1 for even longer and its really the perfect midlayer. Hoodies are very trendy right now, but the hoodless version + a hat works jolly well too!