The wash-in stuff is great and it does keep your stuff breathable..it's designed NOT to clog the pores in gore tex. Now, if you have a bunch of insulation it's not the best chance as it will block flow in insulative type materials. I washed my bibs (outer material and inner liner) and then coat (has a layer of insulation) and the coat made be sweat. The pants still worked great. For insulation stuff, use the spray-on...not as good as the wash-in but will allow you to still have the coat breath. Usually the wash in is used for the bibs and pants and spray on for coat...just depends on if you have the insulation and many coats do.