I had one that was still going strong for 10 years. Sold it when I moved. Had two more that were 5 years old and one that was 14 years old. The 14 year old ballast I had to service a year ago, but they did it for free (should have cost $60). Excellent ballast, and I would not be too concerned with age. Even if it does go out, you can send it in and they will repair it for $60 (or free maybe) and you will have a brand new ballast again.