I completely disagree that the LED is superior in every way. I do agree that they have a lot of great attributes and in many cases, they are a logical choice. I also agree that they are getting closer and closer to meeting all the attributes of the HID, but they aren't there yet. So, HID still has merit. Every tool has trade offs and anyone that ignores that is being silly.
The other thing that drives me nuts is all the touting that an LED will last for ever. Everyone is quick to quote the MTBF (mean time between failure) or average life of the LED diode element. And, those numbers are indeed huge relative to other light sources. But, that is only one element in the system and comparing that to an HID bulb is also silly. The LED requires, again relatively, a complex drive circuit to make it work. And, the MTBF of the LED is only valid if the drive is well within set parameters including getting the heat out of it. And, this applies to the complete chain in the drive circuit. Just because the light is underwater doesn't solve the problem. The design has to provide a path to get rid of the heat. LED/driver systems should be compared to HID/Ballast systems. I know must people understand this, but all I ever see is the LED has 50,000 hours (that's six years of burn time or about 32 years of diving 5x/week at 2x/day at 3hr/dive).
I think LED lights are great and well done ones are a great solution. I have dove Dive Rite, Green Force and Light Monkey. But I'd like to see some better practical estimates of the reliability of them. My dive lights have been pretty good, but my land LEDs haven't been so great. I suspect switch issues in some and battery connection in others, but even a nice Sub Gear light has given me erratic performance. And, I have had failures in various LEDs for cabinets, closets, aquariums, etc. I didn't have any failure analysis done, so I don't kown if they were LED or drive or switch, etc. I GUESS that they are related to overheating, but they might be cheap components or other design flaws beyond heatsinking.
Okay, I settled down, rant off
The other thing that drives me nuts is all the touting that an LED will last for ever. Everyone is quick to quote the MTBF (mean time between failure) or average life of the LED diode element. And, those numbers are indeed huge relative to other light sources. But, that is only one element in the system and comparing that to an HID bulb is also silly. The LED requires, again relatively, a complex drive circuit to make it work. And, the MTBF of the LED is only valid if the drive is well within set parameters including getting the heat out of it. And, this applies to the complete chain in the drive circuit. Just because the light is underwater doesn't solve the problem. The design has to provide a path to get rid of the heat. LED/driver systems should be compared to HID/Ballast systems. I know must people understand this, but all I ever see is the LED has 50,000 hours (that's six years of burn time or about 32 years of diving 5x/week at 2x/day at 3hr/dive).
I think LED lights are great and well done ones are a great solution. I have dove Dive Rite, Green Force and Light Monkey. But I'd like to see some better practical estimates of the reliability of them. My dive lights have been pretty good, but my land LEDs haven't been so great. I suspect switch issues in some and battery connection in others, but even a nice Sub Gear light has given me erratic performance. And, I have had failures in various LEDs for cabinets, closets, aquariums, etc. I didn't have any failure analysis done, so I don't kown if they were LED or drive or switch, etc. I GUESS that they are related to overheating, but they might be cheap components or other design flaws beyond heatsinking.
Okay, I settled down, rant off