I have just completed a major update on my 12,000 square foot office building where we removed the old T-12 fluorescent bulbs, bypassed the ballasts and then installed Lifebulb's 4 foot LED 1800 lumen bulbs. Wow! It is unbelievable how bright and clear the building lights are now. And the 5000K daylight color is nice and clean compared to the old yellowish dimmer lights that we replaced. All this and my electricity costs just dropped by 70%! I should have done this sooner. After thoroughly researching and testing three other brands, the Lifetbulb LED option was the clear winner. They are built much sturdier and are clearly better quality than the others and they have a 5 year warranty. I could not be happier. Lifebulb makes the best LED on the market. You will not be disappointed. While its more time consuming to bypass the old ballasts, that installation will clearly save the most in electricity as I went from 40 watts to 12 watts by using this installation option. And 1000bulbs.com will clearly give you the best price online anywhere. Their customer service is nothing short of excellent. Ask for Allison as she's very knowledgeable and was wonderful to work with. Overall, a superb transaction.