Diver294: We use these on every dive - not just night dives. I personally found myself saying (often, really) "I wish I brought my light..." only to have left it on the boat. That's what started it for me - I wanted to integrate the light into my rig so it was always with me. For me, it quickly evolved from a piece of sight enhancement gear into a piece of essential safety gear. I use it to keep in touch with my buddy during a dive...we communicate all during a dive with our lights. No more neck cranking, no more "is my buddy still there" stuff. If he/she needs me, a coupls of quick swoops of the light and I'm there in a jif, and vice versa. I won't dive without one now...I consider it as essential as my regulator.
ABQdiver: I heard the same thing, for the early ones. But I've had mine since Feb this year, and have had no issues with the head. The only issues with my light have been my issues (like forgetting to charge it once...) All else has been perfect. There are tone os people here who have this head and have had perfect performance, as well.
K