I got a box of boxers and they're quite nice. I do wash them after every use, which makes sense. Got a bunch of socks too, they're great, especially since I'm prone to sweating in that area. They do start to show some wear after two years, which is exceptional given the abuse I put them through with skateboarding.
I'm wondering how it'd work with underwear though, as that's probably something one might to wash after each use regardless of material.