Yep, EJ-92606, I am talking about QH headlights' performance ~ that is, how well they illuminate the road. The question of how long a QH bulb lasts, is of course relevant and important. For most bikes on the road, a QH bulb should last 400 - 800 hours or so. That's quite a helluva lot of miles . . . shall we say 10,000 to 40,000 riding miles, before you have to dig into your pocket for a $5 ~ $10 replacement? (Assuming you haven't troubled to carry a spare bulb in your kit.) Now, we have all heard of a certain unnamed twin-cylindered bike which can sometimes manage to blow QH bulbs in surprisingly short order. Perhaps I am being unjust, but I tend to blame that bike's designers for the short bulb life (rather than blame the bulbs themselves) ~ somehow, by some means of electro-trickery, they have managed to sabotage the normal bulb life expectancy. Now again, if they can sabotage the humble and simple QH bulb . . . can we trust them not to sabotage the "normally expected to be far longer" life expectancy of a diode-circuitry or HID-ballast-box ? I am hopeful . . . but I am uncertain whether the fan on the LED headlight is a sign of careful design or of a worrying weakness. [And how reliable is the fan itself?] Personally, I would like to have a headlight system with hybrid QH + LED elements, with enough redundancy so that I can keep riding at fair touring speed, even when one component has expired. Maybe you call that "reliability" or maybe you call that "resilience" . . . when you are far from the nearest corner store.