Lightweight and comfy
I wore these quite a bit on my most recent trip to Alaska as a wind breaker and for rain protection, even though we got quite lucky with the weather and it never poured cats and dogs.
I love the Goretex material! One day, my lightweight hiking pants got a little wet while canoeing. Back in camp, I just put on the Alpha SL pants right over my wet hiking pants and a couple of hours later, I was completely dry again. The entire time, I stayed quite nice and warm. Another day on a strenuous hike, it never got too hot - hooray for Goretex!
I also like that there's a fly. No pockets though!
For me, it was between the Alpha SL and the Marmot Minimalist Pants. I decided for the Arcteryx, because it had a little more room (allows for more layers underneath) and a fly.