I was wondering if anyone has experience with Slumberjack sleeping bags.  Specifically how their temp ratings stack up are they spot on or more  of a lower limit?  Even more specifically their -20 bags either the Lapland or Sojourn.  I am looking to do a couple of winter endurance events next winter at least one event has a requirement of a -20 bag it has to be a singular bag not a sleep system. All the events have dedicated shelter checkpoints along the way the bag is more if something happens and the participant has to bivy out over night.

I have owned several of their better synthetic bags over the years.   I always found them well made in the past.    I also found most of their temp ratings a bit optimistic, in my opinion.

Most of the bags I use today are down bags from Mountain Hardware, The North Face, Sierra Designs, and Western Mountaineering.

We just got my kid a soljurn 40f.
Its dri down. Sub 3 lbs.
It's got some good features I like.
Big zippers.. good dual side zips.
Abilty to zip down and then stick your arms out and then Velcro the top back down. Aka..able to work from the bag. Big baffles by the zippers..
Came with stuff sack and mesh storage bag.
Irrc it's also treated for water repellancy.

I've only had zero f bags from them in the past. And they were nice. This bag for what I spent 60+$ seems ok. Least in terms of construction.
I purchased one of their backpacks last year and was surprised at it's quality. I expected shit lol.

I have one of their packs and consider the quality and construction top notch...  I don't own one of their sleeping bags though...

I have two Slumberjack bags, one rectangular rated at 40 degrees F, the other, a mummy, rated at 32F, both, in my experience, fairly accurately. Asked their rep at the ShotShow a few years ago about their temperature rating protocol, and while the answer was ambiguous, results seem OK. These bags are well made, thoughtfully detailed, remarkably light and  compressible, valued components of my camping kit.

Woot.com has then on sale now 69-89 for the sojourn and another model.

i have an older -20F Slumberjack bag.  I have used at well below 0F in BWCA but never down to a full -20F and was toasty warm.  Always say...."comfy in my slumbee"

Jeff

Same here though I think mine is a 20* bag and it's a rectangle one.