I wasn't able to find much about this so I thought I'd ask: has anyone used an elephant foot or other short bag and puffy for their sleep insulation here?
I'm contemplating it because I am warming to the idea of wearing more of my insulation to sleep. Maybe I just like the idea of technical pajamas. I don't see this system saving me any weight, but only shifting it into clothes I can wear in the evening and morning.
Either way, I don't like to get out of the down cocoon in the morning, even less at night after I've tried to drown a salty dinner with more than my usual water intake. Also, it does seem logical to wear the puffy and pants I already bring instead of just keeping it handy.
I'm just wondering if there are any caveats before I make the leap into a smaller bag. Or into a smaller quilt. MLD makes a half quilt that might work, too.
I have used an elephants foot many times. It is primarily designed for climbers. You pair it with your down jacket. IT is not very useful if you do not have a good quality jacket with hood and you have to have good gloves too.
This is my husband's choice of sleeping system, even though we no longer climb (he is extremely claustrophobic and cannot stand to have his arms enclosed. He had is made to specifications by Feathered Friends. And yes, I am totally envious when he gets up in the morning staying toasty in his big down jacket. He generally sleeps warm so most often just lays the jacket over him- rarely actually puts it on at night.
It is hard to find a commercially available elephants foot anymore. The original idea of an elephant's foot was to reduce weight, for bivy on big wall climbs, since climbers usually took down parkas anyway. Now that the newer lighter 800 down bags are available, elephant's foot bags have fallen out of favor. If you are a cold sleeper, you may find this system less desirable.
One unusual advantage for me- it doubled as a sleeping bag for my babies until they were about 5 years old. I actually sewed my own. It was a synthetic. They are actually quite easy to make because there is no zipper.
If you are simply trying to add some lower body warmth to your current sleeping bag, I would instead get down pants that can also be worn around camp. I also find that in most conditions, my 4 oz down sweater in the morning works just fine to wear when out of the sleeping bag.
The total weight of my system now (down bag plus light down sweater) vs. my husbands, expedition jacket with elephants foot, are about the same.
One other advantage of the elephants foot-parka system is that you can take different weight(temperature rated) jackets for your top layer. This makes the system quite flexible. Be aware that quality expedition jackets are really expensive!
If the elephants foot were an obvious advantage, I would think it would be more popular. For the same money, I think you can get a warmer overall system with just a sleeping bag.
I was fortunate enough to work about a mile from a Golite store just before they closed shop and snagged an 850fp Bitterroot on closeout. Super warm. And I just grabbed a set of synthetic insulated pants and down booties because I was already planning on supplementing insulation. So, that's covered.
It does seem like elephant foot bags are pretty rare and expensive, so I guess that's why people aren't as excited about them. I have to admit that the idea of not pulling a puffy layer of down up to my chin sorta feels wrong, but I think I can learn to live with it for the relative gains in versatility and getting a little pack space back.