I tried a Moonstone Nada several years ago. I don't think it is made anymore. It was hard to get into and out of. If you wanted to move around during the night it was hard to keep it in the top up/bottom down position. Hard to zip up and unzip a sleeping bag with your arms pasted to your side. Had a lot of condensation. If you sleep on your side instead of on your back it does not work well.
One trip convinced me that it was not for me. It was only a few ounces lighter than my tent where I had room to at least move around.