The Haven looks really interesting, especially if it is as warm and light as claimed. I found some more pictures here. And, am I right in thinking you might be able to sit up in it, sneak your arms out, and drink a cup of tea without most of the rest of you getting out of the bag?! More stuff here too.
A lightweight fleece blanket spread on the floor helps.... Not that I carry such thing with me all the time.
But most of the times there is enough draught to keep condensation at bay. That's also why such a system doesn't work when it gets too cold. A light cooling breeze once a while under your blanket is nice when your sleeping warm. But when it's really cod (colder than -4) then such a light breeze once a while becomes too cold. The rating until -6 is therefor IMHO bogus. With such temperatures it's simply not comfy anymore with the once a while breezes under your 'down blanket'.
700 fill power (iirc)? And presumably US 700 fill power at that!
What is the point in designing such a specialist system, and touting it as a lightweight high performance thing, and then using such 'ordinary' down in it? I'd be looking for European 800 fill power (at least) in such an item, either to increase the performance further or else get the weight down more....
Five years ago you should have been extreme happy with 700 EU fillpower down. It's a 'technology' thing of the last couple of years bag makers are able to sort down so good that even the bestest down can be selected so that batches of down can be selected with fillpowers that reachin 900-ers! Ofcourse it's better, less weight for same insulation (more loft).
But it's still the big question if high fill power down lasts just as long in durability as for instance 700 fillpower down. Presumably high fillpower down is because of the extreme good loft also more fragile... Time will tell.
700 grade is just fine, you just need some more down. But not necersarily way much more than 900 grade down.
am I right in thinking you might be able to sit up in it, sneak your arms out, and drink a cup of tea without most of the rest of you getting out of the bag?!
Judging from the photos, only if you, a, have extremely long arms, and, b, you don't mind a b***dy great draught around your back.
Frankly, to me, this looks like a faffy bag that would be horrible to sleep in.
"It's aimed primarily at lightweight obsessives and adventure and mountain marathon racers."
Then it's probably doomed to failure - it's almost twice the weight (and £10 more expensive) than the Phd Minim, and 50% heavier than the Minimus (which has kept me comfortable down to about zero C).
