How well the Cascada jacket would cope on a windswept torrential rain lashed Rannoch moor (or a nice summer day in Scotland ) I can’t say.
But I wore that jacket through some pretty grim days and it’s performance was excellent.
I have looked on the Paramo site and they recommend washing the jacket with Techwash every 4-8 weeks of regular wear. That seems very excessive and expensive to me. I never washed it once and it still worked OK for me.