Just got mine, and took them out for a (very, very steady) pootle around Gisburn yesterday, in constant rain. My arse was pretty much the only bit of me that wasn’t wet – a little bit of sweat moisture, but you can’t really complain at that. Been a bit of a revelation to be honest.
Would agree with everyone above on fit, I’ve got a large and kinda wish I’d gone for a medium, but you can cinch them up a bit with the velcro pulls, and in fairness they didn’t fall down. Fine over Bluegrass kneepads, which are enormous. And no problems with upwards water ingress at all.
Can’t comment on the longevity, but based on yesterday I’d recommend them. Dry arse is a revelation 😉