I dont think the sulfur plasma tech is going to be avalaible for flashlights. Since it was invented in 1994 (if i remember well), efforts to make it avalaible in low wattages had failed. In the last two years, this conception has been developed a bit more and its been commercialized.
But, for what i know, the high efficiency just happen in the high wattage models.
It would be nice a portable sulfur plasma system, but i believe its very difficult to happen. This technology has suffered a lacking of fund for research, and i dont think its going to change, cos most lighting companies are concentrating on LEDs and OLEDS.
Sulphur plasma, are you working in smaller versions? Or its basically intended for fixed lighting?