Far as I understand the physical issues, all "waterproof" membranes or sprays represent a trade off between three axes: Breathability, water resistance, and durability. Agree that coupla brands breathe bit better than Gore Tex. (Think we had a thread years ago that included charts of tested permeability.) Dermizax, AFAIK, is a factory coating. Works well but dies fast.
But IME they also let more wind and water in, which follows from issues of pore size and confirmation, and they don't hold up as long, which follows from issues of thickness and mechanical strength of the vapor barrier, which is what dies first. So I have lighter, more breathable parkas for backpacking, skinning, and summer travel to hot wet places; one is GT, one is not. I have heavier, more durable parkas - both GT - for typical winter skiing conditions. Which rarely include lots of rain but often include icy wind, not to mention falling or banging into tree branches. So for 5-7 Benjamin's I want a membrane protected by something on either side. YMMV