Well, my 2nd 1000 watt ballast died today- so I've lost 2 large ballasts in a matter of a week. This one was an iPower, bought in November, 2016. So the 1st iPower ballast lasted 2 1/2 years, and the 2nd lasted almost 3 1/2 years. The fuse button kept popping, now it won't even fire. For under a $100 each, not too bad i guess but they do produce less lumens than many of the others. Thank god for Amazon Prime- the replacement (Tophort) will be here by Sunday (Easter!). In comparison, the Lumatek's- were about $275 each- one lasted almost 3 1/2 years and the 2nd lasted just about 5 years. And they were way brighter than all the others.
So, I hooked up a cheapy, no-name brand 600 watt HPS to replace the 1000 watter until the new ballast comes.......not the end of the world for 2 days.
To further comment, I think power surges (which I get a lot of in my rural area) shorten the bulbs and ballasts lives. The more surges, the less life. I'm a stones throw from the Chesapeake Bay, and get a lot of wind here right off the water, I think that's what's always causing the power surge issues.
Otherwise, all is good here for now.