Also, if you go Google "400W 1000W HPS LED Study" there was a study done where a few biologists and horticulturists grew in these conditions.
1.
1000W HPS
2.
400W HPS
100W LED surrounding it on 4 sides
And they claimed that the 400W worked the same as the 1000W, with the added benefit of better light penetration, meaning more branches getting more light making bigger nugs everywhere, instead of just mainly at the middle of the HPS like it does with HPS, they called the HPS good spot on the plant(s) the "sweet spot". But the LED/HPS combo gave more nugs, as well as more trichombes.
And I am doing a combo.
So I wouldn't say that the wattage is really important at all as long as you have enough. And I have enough, plus I will probably get a CMH soon, which is equivalent to 1000W MH, and CMH is just Ceramic Metal Halide (MH is Metal Halide for the benefit of anyone reading who does not know). And something like 315W CMH is 1000W MH because less Wattage goes to heat. And LEDs don't give off as much heat either, so it's also possible that the added wattage benefit I am seeing that is greater than actual wattage is the heat benefit. And I am just saying that it's better than actual wattage, I am not saying 1500W LED is equal to 1500W HPS, but it is higher than its actual wattage compared to HPS. I think LED 1500W is like 350 actual Watts, and I would say that 1500W LED is way better than 350W HPS.
But with Ceramic Metal Halide they are actually the same type of light, but just a different material allows the bulb to not heat up so much, which allows 315W to be 1000W, and there aren't as many haters out there disputing that.