OM, these are fairly new (within the past few years) and are touted as being made with a breathable material that doesn't trap moisture.

I've not used them, but I got a hands on look at my buddies. They're not just an emergency blanket made into a bivvy. They're really pretty interesting. If you're out in temps that are pushing the limits of your bag these seem to be a good option. Here's a video:

Thanks aimless, for clarifying.

billstephenson, while they may be breathable, I doubt they are very breathable. Emergency use only?

I've been wanting to hear from those that use them since they were introduced. My neighbor is the first person I know that has, and that's only been one night. So I personally just don't know how well they work or breath.

The night he used his it got pretty cold, probably around 26ºf. He woke up about 4:00 in the morning and put the SOL bag inside his sleeping bag and stayed warm the rest of the night, which was still getting colder. He said he had no problem with condensation inside the bag. That's all I really know for sure.

I think that SOL bag would be great for taking on day hikes for emergency use and for bringing when the low temps are forecast to be near the rating (or personal experience) of where your bag isn't warm enough.

For those reasons alone I would use one a lot, so I'll probably get one for our next season.

“…even if the klymit static V …”

Sorry for the late post
The Static-V pad isn’t very warm.
The neo-air is lightweight and warm IF AND ONLY IF it’s pumped hard. I’ve used the neo-air on 20F nights with my 20F zpack quilt/bag and was fine with socks, long john, balaclava, and hat.

Down at 0F, I use the GG CCF pad only. Even though it’s a 2.0 R rating it still works great on snow. And the snow makes it much more comfortable. W/o snow, I could not handle a CCF pad alone.

Sleep well,
-Barry
-The mountains were made for Tevas

Yeah, the R value is only 1.3 (for the static V). I'm hoping it is fine for the 30's.