Most Cree leds are rated 50,000 lifetime hours which means after 50,000 hours their luminosity will have dropped off 30% from a when they were new. So if they put out 100 lumens new after 50,000 hours on average they will put out 70 lumens. I looked up what the the xp-g leds (since that is what I am using) state and noticed that they shortened it to 35,000 hours, but that is still almost 8 years with 12 hours on.
In my opinion 2-3 year replacement cycle for leds is unacceptable for the high upfront cost and the pain of replacing 50+ leds. Of course it is a function of you get what you pay for and Cree is more expensive, but also the most reliable with highest efficiency (135 lumens per watt on xp-g). Hope that helps.
In my opinion 2-3 year replacement cycle for leds is unacceptable for the high upfront cost and the pain of replacing 50+ leds. Of course it is a function of you get what you pay for and Cree is more expensive, but also the most reliable with highest efficiency (135 lumens per watt on xp-g). Hope that helps.