I lived in a gaijin house for about three years. It was located about a five-minute walk from Ishikawacho Station in Yokohama. Unfortunately (actually fortunately!), it was purchased by an individual and has since been converted to a private residence.
But to comment on gaijin houses in general, I enjoyed my time there because of the convenient location, the people I met while living there, and the flexibility it provided with regard to my living situation, so overall I think a gaijin house is a worthwhile lodging option to consider while in Japan!