I too use this as a ground sheet, bonus is my pad doesn’t slid around on it like tyvek.I have one. I think it is hyperlite mountain gear. Works fine. Fairly durable. It is small and light. 4-5oz. It also costs over $100. You probably save 4-5oz over a comparable nylon or thyvek sheet. If you are an ounce counter it might be worth it but it is an expensive way to trim a fairly small amount of pack weight.
i like and use more a thing from seek outside called a matty mcmat face. It is a very thin pad. I cut one to 25” wide and it weighs 6 oz. it is a ground cloth and a sit pad.
i do the seam sealant trick on my sleeping pads. Makes a world of difference !I wouldn't recommend using Dyneema or cuben fiber as a ground sheet and then as a tarp. You will get tears relatively quickly. The stuff is strong in terms of tear strength but is sucks for abrasion resistance. Tyvek would be better and you can get stick on tabs to rig it for an emergency shelter in a limited sense. Silnylon works too but its slippery. Seam sealant can be put on it in small strips or dots to prevent some slippage.
I use a 1/8" foam pad from MLD now. Seek Outside also sells them. 8oz and has a ton of uses. Emergency sleeping pad, nap/sit pad, and protects my sleeping pad from the ground.i do the seam sealant trick on my sleeping pads. Makes a world of difference !