Nikwax TX.Direct - does it work?

[Dan00001]

Not quite so, Sympatex and some PU coatings operate on a different principle. They can pass water as liquid through but they work best with a fairly large temp gradient. Their breathability is not as good as some of the holey membranes but they are mechanically stronger. Sympatex at least seems to work much better in shoes than GT.

Just re reading some of Keeping Dry & Staying Warm and it does actually briefly mention Sympatex. It says it relies on it's hydrophilic nature to transmit sweat outwards. It also says it's very sustainable because the whole garment is recyclable.