I no longer carry one, but only because its been replaced by the multifunction wonder that is the Jerven Fjellduken, produced by those clever Norwegians. I throw it on as giant jacket, or just a blanket when taking a rest stop and use it to protect my sleeping bag from hoarfrost when in snow shelters, were I often configure it as a sleeping bag type garment with arms when cooking or organising kit, I also have the peace of mind that should an ice storm blow in and I cant make it back to camp, I can climb inside and sit it out.
I use the Multimate model, which allows me to remove the insulating liner and use the outer as a standalone tarp.
Unfortunately they are very expensive, and the multimate model that I use (with the removable liner) no longer appears to be available to the public, though its still in service with some units of the Norwegian and Danish military.
I wrote a review for BCUK a few years ago, the articles area of BCUK is down but the review is also reproduced on the Jerven website and in their catalogue:
https://jerven-com.secure.flexiweb.no/page/7366/