J!NS has opened a store in Union Square in San Francisco. They are also opening stores in Santa Clara, CA and Arcadia, CA this summer. Though I haven't done a direct comparison, the US pricing doesn't seem as inexpensive as it is in Japan.

We have an optometrist friend that buys her own glasses at J!NS in Japan rather than in the US because she finds the fit of some J!NS frames to be much better for her (low nose bridge). I'm thinking of getting a pair at J!NS on my next trip to Japan.

If you are a Costco member, all Costco Japan locations now offer same day service for stock lenses, and may be done in as little as 30 minutes. I had a pair of glasses with progressive, high-index lenses mounted on rimless frames done there, and I'm very happy with them. However, my order had to be sent out and took a couple of weeks because they didn't stock lenses for my level of astigmatism.

http://www.costco.co.jp/p/10348?lang=en