Worms Way just featured a plasma light in a side by side with a 600 watt HID. They recommended light replacement every 9 to 12 months, mentioned the efficiency benefit on operating costs over HID. I was taken aback by their $999 price for the whole unit. Seems too expensive to me. First time I have been exposed to this type of lighting. If they could get the price point to under $500, it might be a good move. Claim it satisfies veg and flower spectrum needs of the plant and can be placed closer to plant tops with less heat.
The cost of a plasma is not that much.
A Gavita LEP 300 you can buy for $1300.
I think that plasma is great to use together with hps.
The extra UV-A and UV-B (they filter out the UV-C) will create more and trichomes.
It doesnt make big buds.
It does make better quality.(more and better thc)
The PAR level for the Gavita plasma seems to be right in between a 600W and 1000W HPS (when measuring a quality bulb like a horti) and when compared against a value 1000W it is about the same, if not better.
It is not recommended to run them more than a foot away from the canopy. I would guess that if people use them the same way as a standard 1000W they will be disappointed. same as when 600's came out (small, loose buds). It looks like the inverse square law really comes into play. and an extra 10 inches of height will probably make a BIG different in mass. With an HPS not so much.