I was skeptical too, before I joined Pivotal Labs, but I love it. It's worth noting that it's a skill, or rather a collection of skills, that are much easier to learn from an experienced pair.

At the moment I have been on a solo allocation for about 6 months. It has let me go down a lot of rabbit holes, which can be educational. But I miss pairing pretty badly on days when I am working on straight regular development.