I kept asking what is this Insultex stuff? Took the gamble, and this weekend used Mac's MacIX while paddle camping in the Smoky's.
Let me preface by saying I'm a COLD sleeper. The first night I fell asleep and slept soundly with only the single layer MacIX under me. I slept until 0400 and woke up a bit chilly-not cold but feeling the differential. It was 46F and I added a second layer under my torso. The second night I fully deployed the hammock sock from HF member Unsponsored but the second night was much warmer and I slept until the storm hit in only my camp cloths (thermawrap pants, fleece top) with the MacIX below.
The MacIX delivered to me weighs 4.4 ounces! As delivered to me it is the perfect summer UQ, with a second layer of Insultex I can see spring and fall added in, a 3rd layer and down will get a run for the money
For paddle camping the synthetic nature speaks for itself.
I def. think Mac has got something here.