S1XXV FGR.png S1XXV FYE.png The Ibanez S1XXV 25th Anniversary is a Limited Edition S series, Premium series electric guitar model produced for only a few months in 2012 to celebrate the twenty-fifth anniversary of the S line. The S1XXV 25th Anniversary was made as a tribute to the original 540S (needs confirmation). From the factory, the S1XXV ships with color-matched DR Neon strings.