I used to use Phantom when I ran HID. Only had one ballast go out. It was 2.5 years past when I purchased it. Phantom(at the time) warrantied their ballasts for 2 years. I contacted them and they told me to go to a local shop and grab one for free. They replaced the shop for the one I grabbed.
I still have one with a hood and a Hortilux on standby in case one of my LEDs has a problem.