I have an old Sigma HD 28 made in Japan for Martin back in the early 1980's. It is an excellent guitar. It has a spruce top, rosewood back and sides, and a mahogany neck with a rosewood fingerboard. Made the old fashioned way before CNC and finished in lacquer rather than today's cheaper looking satin finishes that are common on popularly priced guitars. And I have it strung 10-46 like my electrics so I can do blues style bends. Despite the light gauge strings, it has a wonderful deep tone and almost never goes out of tune. I would not trade it for a modern day Martin or a Taylor. Today Sigma's are mostly machine-built mass-produced guitars, but back in the day they made a real effort to retain Martin standards of quality.