About 20 years ago I bought a new 12 string. I told the man running the music store that I wanted to tune it to concert pitch. He said that he had a FG512 Yammie that had a lifetime guarantee. I liked it and so bought it. I kept her 440'd ever since and it still has a lower action than my three 6 stringers. I never used the warrenty but I believe that Yamaha still stands behind it.