Video at Amazon.com view compared CUBELIGHT II from Sigma (yellow light) and von Busch and Müller IXON IQ (the white Lich)! When Ixon IQ Lux is repeatedly changed in the Power mode with 40 Lux from City Mode 10. Even in the City mode, the CUBELIGHT II has no chance. The video will convince everyone of every day by bicycle is traveling and has long studied the right lighting! I have not regretted the purchase, even if the price is slightly higher.