@collective Induction lights are also used for outdoor lighting such as roadways to replace MH, and are seen to produce more light at distance. Since the light spectrum is better suited for plants, the light that does reach lower should be of better quality than a similar HPS, even if the HPS is somehow distributing 4 times the light. Testing just now, the 400W Indagro puts out about 6k lux at 4' directly under the bulb. After purchasing my Indagro, I found some induction bulbs available for about $1/watt whereas the IG was $1.75/watt. They come with a half the warranty(5 year). I will likely purchase somewhere between 200-300W circular bulb w/ reflectors to finish the garden.
Consider, even if you had 2 x 400W indagros to replace your 1000W HPS you would still save a ton on lighting electricity, let alone bulb replacement, cooling, etc., and have waaay more light, but supposedly one 400 is enough to compete with 1000W HPS. I hope to get good results with my trees, but I am topping like crazy to get colas like "oregonkush" on youtube. (who uses 1000W HPS, lol)
If you have the chance to change lights out you should give it a shot as the elec savings pay for themselves handily, especially if you're in California.