I've made the Slipped Stitch Rib Socks before, but I don't remember them working up so quickly. Last time it took me five months, this time it was just under a month.
I especially like how the gusset looks a grid of tiny little squares.
This yarn is quite lovely. It's KnitPicks Stroll, which I expect to be durable as it's 25% nylon. It's soft and comfy and comes in a variety of beautiful colors. I received it as a gift, but I'm sure I'll be buying some in the future.