Halogen ballasted mercury lamp full power

Here's the lamp at full brightness. Now the mercury is very dominant, but the halogen still provides enough light for colour rendering. The combined colour temperature is between 4000 and 5000K. My energy monitor showed that at 241V, the lamp pulled 291W and 1.26A with a power factor of 0.96. Which makes me question whether it is truly a 250w lamp. On the whole, I'm rather impressed with these lamps. I wouldn't want to test them in actual street lighting, but as a novelty I quite like them.