Philips's does best

The LED lamp with GU10 socket replaces a 35W halogen spotlight very good.
The brightness corresponds even more an aged 50W halogen spotlights. With only 4Watt power remarkable.
What has impressed me most is the light color. With 2700K to match the warm white halogen light. Nevertheless, I am very sensitive to the light color. No other manufacturer dominates the mixing of substrates that are responsible for the color of light as good as Philips. No annoying greenish or pink tinge, but they like to see in competitors. The Philips could very well already with the fluorescent lamps. Only during dimming below 50%, the light color no longer acts as natural as the halogen lamps, the yellow-orange is always basically.
The color rendering index is indeed stated rather poor with 80, but I feel him subjekiv far better than the typical 80 Some energy-saving lamp.
Very nice is the delay-free switching. This may well not every manufacturer.
Meanwhile, I have 10 of these radiators in use and am completely satisfied.