We've just this moment got our grubby little paws on the new
Crux Torpedo eVent-shelled sleeping bags which are due out next
month, May 2008.
The new Torpedo is, says Crux, 'absolutely for climbers' and
essentially is the equivalent of a bivvy bag and a sleeping bag all
in one. The outer shell is made using eVent waterproof and breathable
fabric with seamless baffle technology keeping outside seams to a
minimum, those which there are, are taped.

The down used is top notch EU 850+ fill power stuff from Poland,
for exceptional warmth to weight ratios and there's a three-quarter
length zip. Vee-tube baffles maximise efficiency and there's a full
neck baffle as you'd expect.
Three versions available - the 500 rather down to -10C, the 700
down to -20C and the big daddy Torpedo 900 rated to -30C and aimed
squarely at Himalayan use. Weights are1050g, 1250g and 1450g
respectively and prices £330, £395 and £450.

It's all very impressive stuff, but we can't help feeling that a
water-resistant zip would have made more sense than the standard one
fitted plus the conventional sleeping bag hood design means it's
never going to be as weather resistant as a stand-alone bivvy bag in
wet conditions.
Is the Torpedo and better solution than a sleeping bag / bivvy bag
combination? We honestly don't know. Certainly in wet conditions a
bivvy bag ought to give more protection, but in snowy alpine
mountaineering bivvies, the Torpedo could be an excellent balance
between protection and weight saving albeit at a price.
More Crux things at www.crux.uk.com.
Apologies for the dreadful pics, in essence it's a big black sleeping
bag with a red lining :-)