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There are a few misconceptions in this thread.
1) LEDs have an effectively unlimited lifetime.
Nope. Ain't so. While the little indicator LEDs used in most of our appliances will last long after the rest of the appliance has failed, the superbright oversized LEDs used for traffic signals are another thing entirely. In order for them to produce enough light, they are run over their optimum voltage, which shortens their lifetime considerably. They do last longer than incandescents, and they are more efficient, but not overwhelmingly so.
2) Fluorescent lamps. They never did produce pure white light, and they don't now. The cheapest varieties (like those used in most offices) produce very poor quality light deficient in the red part of the spectrum. This is regardless of whether it is "warm white" (low color temperature) or "cool white" (high color temperature). The flicker from a cheap ballast (nothing but a simple inductor in a 280V lighting system like those in most offices) is at 120Hz, not 400Hz. Electronic ballasts and high CRI (color rendering index) fluorescents are available, but definitely not cheap.
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