So an HPS bulb is allegedly supposed to last 20,000 hours? I have 9 total lamps, all 250 watt hps and one went at 4,000 hours, and now I have another one that is on its last legs (lighting and re-lighting, won't stay lit) at 5,000 hours. The others look good right now but they weren't all bought at same time, they probably only have about 3000 hours on them if that. The bulbs were both Ipower, anyone have a brand that is better? I don't care what the cost is I just want one that will last. Another question, what if I were to put a stronger bulb in like a 600 watt or something, would the life be extended operating at low power? I know putting a smaller bulb with a large ballast is a huge no no but don't see what the harm would be other way around. The 600w would essentially be operating at 40% power. It is really a pain to change my bulbs the way I have my setup, so would like to avoid this for as long as possible. whatever way I can do that.