I can see how such lighting is cost effective

Just converted 60 or so metal halide wall packs to curly flourescents. Saved the 150 watt , but left the ballast and capacitors installed.

I can see how such lighting is cost effective for commercial applications, Halogen bulb but plain old incandescents or the newer flourescents seem more cost effective and reliable. Of course the is nowhere near the same, but it is adequate for nightime security and the consumption should be about one seventh.