In reply to TobyA:
> It's interesting, here on UKC I think I've seen more complaints about eVent over the last, say, 15 years than I have about Goretex - it does seem that us punters seem to find that eVent suddenly start leaking in a more dramatic way than Goretex does. But then Gore has become a bit of a behemoth in terms of marketing and advertising, which must be a big part of it.
Funny, because as far as I could find, eVent was about the same as original GoreTex - pure ePTFE microporous membrane, which apparently looses waterproofness once the hydrophobic ePTFE gets dirty, getting hydrophilic ("water-loving") stuff like dirt all over and letting water through (pores "smaller than a water droplet" is pure PR nonsense) and started to leak. GTX apparently started adding a second, non-porous PU plastic membrane (lowering breathibility) that stops the dirt in later generations or laminated a second, sacrificial ePTFE membrane to the first (in the latest GoreTex Pro).
It still (apart from the "membrane on the outside", which is a wholy different can of worms) depends on the outer fabric DWR to work, like any other waterproof. Since for most uses I am more concerned with breathibility than pure waterproofness, it's a pity that there are less alternatives as the PR machine trumps everything else. The biggest breakthrough in waterproof clothing would be a much more durable DWR treatment (and some do look promising, although how much of it is just PR again is hard to tell now), and cheaper electro-spun plastic membranes (once - and if - their durability gets "ironed out").
BTW, for me, Gore is for mostly about pretty marketing (and possibly unfair business practices like allegedly threatening gear makers to drop competitors products, which is I think still under investigation in the EU, while the FTC case was dropped) than anything else. The "membrane contains pores smaller than a water droplet, but larger than a water vapor molecule. So rain and snow can’t get in" is pure PR - this is not how the physics work. The waterproofness of a microporous membrane comes from its hydrophobicity and surface tension of water (just like the fabric DWR) and gradients, not the pore sizes. There is no magical physics-defying membrane that works only in one direction. If the membrane loose hydrophobic properties, if there is more humidity or higher temperature outside that inside, the magic stops.
Sure, it works, as long as the outer fabric DWR works...
Post edited at 12:20