All in all,
My lighting choice for total square footage of 8-9 ft2 would be as follows:
1. CMH, is my choice as the king of lighting. For comparison this is like a bodybuilder who is on a mostly non-red meat based diet with the little steak once a week. For overall yield, overall quality, overall closest natural lighting to the sun, overall broadest spectrum, energy bands in UVA down to 350nm and IR bands out to 850nm. This provides the full range of plant capability from seedling to Harvest. The broad spectrum enables the full range of terpenes and thc potential. Proven to produce over a Pound in 2x4x6 tent with 8 plants.
Cons: While not as hot as an HPS/MH, the CMH does get a bit toasty so keeping it 18” from the plants is required and a bit of airflow over the canopy as always. No hood cooling required.
Top Choice: Hortilux 315W with Hortilux Ballast and Reflector.
2. LED (250W Wall Draw), for very close competitor to the CMH. It would be like comparing a bodybuilder who used only a non-red meat based diet, like chicken or fish. Works perfectly well and gets the results you wish for with zero disappointment. The PPFD is higher with LED than CMH, about 1.5x however this is due to the optimized red/blue (blurple) aspect of the spectrum that all LED companies focus on. Black Dog LED is one of the few companies that introduces a very tiny amount of UVA light into their spectrum. Most companies do not because UVA leds are very expensive.
LED brands range all over the place. Full Spectrum LED is the only way to grow plants properly though. While Blurple works, you starve the plant of potential flavor and other tiny factors that can make buds have a more fine dining wine at 16$ a glass taste compared to the 25$ bottle at the grocery store. Very close in potency, crystal density, and flavor. But the CMH still has about 5% more on average from readings in trichrome/thc density and terpenes. This results mainly from the broader spectrum in the far IR and UVA bands.
Top Choice: Black Dog LED, they specifically worked with cannabis to show that UVA was beneficial in increasing trichrome density and thc. Publications are in my signature highlighting some of these efforts.
3. HPS/MH (600W). This is the bodybuilder who does his chicken, and protein shakes, the diet etc, but skips leg day at times and doesn’t train cadio as much as they should, because they focus on upper body.
These were the standard since the 70’s and aren’t going anywhere. 600/1000W HPS is the mass producer big flower big yields. But man its hot. Requires cooling and ducting or keeping the light high above the plants. This induces a lot of stretching so using HPS you need a fairly tall grow area. With LED and CMH you can get away with a 5’ ceiling and have no issues with only a fan.
Top Choice: Hortilux 1000W HPS. The “old but gold” standard.