I own 6 now. I've ran hps/mh, led, cfls, but $ per quality just doesn't compare to CMH. I run the Dimlux pros with dimmable ballasts and the Phillips bulbs. The PAR light readings of hps at the top of the canopy is the same PAR readings at the bottom of the canopy with CMH, so the myth of their lack of penetration is just plain wrong.
Where you normally get small popcorn underneath, they actually turn into dense nugs under CMH. They are great for veg and bloom making it nice not having to switch fixtures or bulbs. They dissipate approximately half the heat as HPS, use around half the electricity, and the bulbs last around 4 times longer. In my experience. Until LEDs become slightly more efficient and cheaper I wouldn't recommend any other light. I have noticed in side by sides much better terpene production and color changing especially much earlier into flower. Lots of pinks and purples come out under these bulbs without cranking down the temps. Hopes this helps.
Btw you can run them 60" above the canopy all the way down to 36" above. Lower than that without dimming the ballast will give you some light burn until the plants harden off.
