Although I have a strong liking for CMH lamp technology, to me, CMH lamps for street-lighting purposes was a bad idea given the slightly shorter lives compared to HPS. I have seen strings of CMH street-lights being retrofitted within 2 years, due to their bad failure rate, to standard Na-Hg-Sc metal-halide lamps, finally to Philips EnergyAdvantage lamps which have a unique and readily identifiable spectrum. Chicago's CMH 2010 retrofit program of more than 16,000 street and lane-way lights were such a waste.

[Looking for energy efficient lighting for its alleys and streets in 2010, the city of Chicago chose CMH lamps, thus becoming among the first large US city to extensively employ this lamp technology. By August of 2011, Chicago completed installing 11,000 CMH lamps in 482 km (300 miles) of alleys and 5,300 street-lights on Lake Shore Drive and Western Avenue.]

CMH lamps have longer life than Na-Sc probe or pulse start MH lamps.