They do loose some of the light over the years. I read it somewhere online, a guy tested the output after a few years and compared to new ones. Don't know corre

They do loose some of the light over the years. I read it somewhere online, a guy tested the output after a few years and compared to new ones. Don't know correctly, but it was something like ~10-20% of loss in 2-3 years or something. I'm probably way off, but it was definitely not insignificant.