I think that would be the cost of a great led, good leds can be had for about 800 dollars.I'm not really qualified to give any scientific advice about LED's
but I will give an opinion, as often shared by those who have experience.
Although suitable for SOG or seedlings/early veg the LED's lack the PAR
to penetrate through the upper canopy and onto the lower branches, which
works fine if you're growing super small plants. You'll get the bag appeal.
Also it should be noted that the good LEDs cost about $3000..
As an unbiased consumer, the difference in smoke is evident.
I do think these White w/ Far red Led fixtures should be ran at a 2:1 ratio w/ HPS. DE HPS, or CMH in larger spaces. Like my 12x14x10 could use a single 1k DE HPS on a light mover w/ the 4 stationary 650r's IMO and I would be set to grow big ole shrubberies again. like if someone has a 12 lighter baby commercial facility, the it should go row of leds, row of hps, row of leds.
although the LEDs are wonderful and get the job done. I HATE PRUNING AND TRAINING MY PLANTS MORE THAN THE BARE MINIMUM. Mac one, took to them real well, the buds are equally as pretty, and make more smells, but it also, likes to keep its branches up close, so my inners got more wispy and worthy of pruning, because they were all over shadowing each other, increasing my work load.
My patients are telling me that these harvests smoke better than the ones under hps. but I personally couldn't tell the difference between my all led bud, my all hps bud, nd my hps led combo bud.
I honestly think the leds are at this point equivalent to Air cooled(extra layer of glass blocks some spectrum fromthe hps bulb) MH and HPS, for less wattage. I havent used an open HPS or MH in a decade, so I cant say if its the equivalent to bare bulb, or to CMH(the spectrum leds copy) as I haven't used them, or the DE HPS fixtures, and I will not make claims I cant back up.
The 450w spider farmer can be ran at 1:1 ratio w/ the equivalent 1k HPS fixture, in the same room, save money on the bills, and notice no drop in quality.
The 650w hlg board, and any made to the same standard, fully replace air cooled 1k HPS for home growers who don't have silly ceilings like I do.