I spent the last two days climbing on Ben Nevis in a new Jottnar Odin jacket and Vanir LT trousers which I'm reviewing for UKC. They seem very good and tough, but this was the first time I've worn them 'in the field' as it were. I think its very difficult to compare things like breathability and waterproofness, but the material does seem at least as breathable as other top level waterproof fabrics and I think noticeably more windproof than NeoShell. But very early days in terms of using them and it's bloomin' expensive stuff so it should be good!
What actually makes you think that though? I know GE are willing to license eVent to firms to sell under their own brand names, BUT eVent was available when Jottnar started making gear, and they said when they started that NeoShell was the only membrane that they thought was good enough, so I guess Sjkoldr has to an improvement on that.
And I am right aren't I that GE make eVent? Because Jottnar's site says their fabric was developed with a Japanese company, so that also argues against it being eVent.