Nice small but flickering, different colors of light and after a few weeks defective (dark)

The LED lamps do unfortunately only at the first glance impression of high quality. The light acts but very unnatural, which I attribute in part to the very strong flicker of lamps (one sees, for example, when filming the lights with a digital camera). Unfortunately vary the light colors of the four ordered lamps from bluish cool white to warm white. After just a few weeks two of the four lamps have almost lost their luminosity, so it is very dark in the room. In addition, the lamps for LED iambics be very hot.