As Dane said Neo Shell is not hype!
I have the Neo Shell coat Mammut put out and it is the real deal. I have been using in now for a few months and love love love it. A couple weeks ago i did a cold approach to a climb on a 0% morning. I had a Cap 1 base layer, a R1 hoody, then my Mammut Neo Shell then a Arcteryx Atom Lt on top of it all.
I know quite a bit of clothing but it was a cold start and i figured i would shed the Atom Lt up trail a bit. We where moving at quite a clip as we where not sure the climb would be in and wanted to be able to get out and to another climb in such a case. Being the case i never did stop to take it off.
My point is i did a 4.5 mile back country jog with the usual ice climbing gear and 6 inches of fresh powder and the coat never got wet inside. Yes i was sweating quite bad and wet but the amazing thing was no condensation under the Neo shell.
Mind you different Neo Shell jackets are made of different weight and stretch material. For instance the Rab Stretch Neo Shell is like 550 grams and the hand much like a pro shell kinda weight. The Mammut Gipflegrat Neo Shell is more like a soft shell in weight or thicker and 700-800 grams but stretches like crazy and no way in hell you are gonna tear or get the stuff to pull or pile. I can see this jacket still being worn in ten years!
Ow yeah and no way you are gonna get wet in either even in full on rain. I tested that walking the dogs a couple times now.
Gore Active shell is also pretty good but nothing like this Neo Shell from what i can tell so far and also fragile like most Gore Products.