16 years, that's a great score!I have the X479 and for a cheaper priced amp ,Id give it a 7-8 out of 10 rating . I used it for 2) 10" pioneer subs ,Then for a single 15" Lanzar sub. Both setups sound great. Now it's being used for my mids. The year I bought it was around 2000 and it's still going strong .