Well, from my experience with the KP superwash is that it does felt just a tiny bit, but I've used other types of wool blends and they do the same thing. As of yet I've to see if my socks pill up at all. So far they have not.
Wisdom is knowing what to do. Skill is how to do it. Virtue is getting it done.
That which does not kill you, isn't trying hard enough.
I could have sworn Kelly Pitkin addressed this issue on one of the Podcasts Knitpicks has. She said they did pill a little at first, but after that, they never pilled again. At least, I think that's what she said.