now i know why a local parts house dumped their stock of 175w mv lamps at $1 ea.
i bought a case of them as i maintain several yard lights.
i suspect there will be plenty of lamps and ballasts around for a long time.by the time they are extinct we wont care anymore.1000 lm/w led's will have become mainstream.

No light source would ever achieve 1000lm/W, as it would be device called "perpetuum mobile":
- ~550lm/W is 100% efficient monochromatic green light source (in the peak of eye sensitivity), so no light source might exceed this even when sacrificing color rendering
- ~330lm/W is 100% efficient white light source

While the "W" i mean power input in any form (assume even the possibility, then electricity would not be anymore the preferred energy delivery medium; Without this limitation i could say, then the candle has infinite efficacy - as it consume no electricity at all...)