UL Sleeping Bag Recommendation

[Onestepmore]

Someone was asking about the Zpacs 20F bag. We have one, it's great but I'd be cold in it at -7deg C alone. However, I am a cold sleeper, so use a good R rated mat, down balaclava hood and a light down sweater in which to sleep in winter.

[Walking_addict]

simonm and icefest - I have considered a quilt, but I currently only use a close cell foam roll as ground insulation. Would that be warm enough to use with a quilt or would I have to get an inflatable thermarest style bed roll?

Someone correct me if I'm wrong, but I can't see it making much of a difference as a sleeping bag provides essentially zero insulation for the part you're laying on anyway. That said, a warmer mat is probably the most important way of increasing your comfort under cold conditions.

Why I love my Macpac Neve, no down underneath, just right round to the low sides, and the full sleeve under for tapered Thermorest.
Just had it fully rejuvenated after near 15 years of use, and topped off with down (only need 20g to bring back to specs) for Nepal last year, and some extra down in the internal foot bag

Warm as toast at -17c, in a Black Diamond Megamid at 5200m, but did use Goretex bivvy as well.

[Walking_addict]

PS. I know it's a really old OP, but for his plan to use a 2 / 3 season bag and a liner, yes it can work.
I use a Macpac Firefly down booster, great for warm trips used alone, but use it with a regular bag and you can get down to 3 / 4 season solution with a good mat.