I bought this bulb as a replacement for some cheap VIVA brand bulbs that my builder put in the house. The VIVA brand bulbs wouldn't turn on for nearly a full second once the light bulb was turned on. I bought one of these bulbs to test, and the instant the light switch was flipped, the light came on! I also really like the 3000K color. Not as yellow as 2700K, but not overly white, like a 4100K would be. I also like that the bulb has a toll free phone number printed on the bulb, so you know the company is willing to stand behind the product. Couldn't be happier.