In reply to arch:
Just bought the Arctic dream 1200 from Alpkit. 1200g 750 fill power. Comfort rated to -23. Weighs in at about 1700g nice and roomy and I'm 6'. 90kg. Have a look at the Alpkit site. It's lovely and warm!
Plus with an exped downmat it feels super comfy.
Size wise from their website. "Optimum: 5ft11 tall or you have a shoulder circumference of around 128 cm. At this size you are the ideal candidate for this bag. You should be able to easily arrange yourself in the bag, and still have the space to wear an additional down jacket if necessary."
Post edited at 20:04