I asked Kessil what the expected lifespan for these lights. I was surprised by the answer and was expecting closer to 10 years although they did say even more. I figure 10 hours a day x 365 days a year x 10 years = 36,500 hours. No where near the common number of 50,000. I'm guessing it's more the drivers and such that fails before the LED lights.
From Kessil customer support:
"With proper maintenance, I suggest reviewing your user manual, these lights are capable of lasting up to 5 years or even more! In general, LED lights has a burning life span of 50,000 hours in its optimal environment. We have many customers who have shared their experience with us and most customers have the lights up to five years. However, you have to keep in mind that this depends on the regular maintenance for the lights and its environment."