I have been planning to switch from incandescent anyway, so I decided to give these a go.
Long story is that I have multiple bikes. I ride year round to work. I get off of work at 1am. So riding home with the deer and the drunks is a challenge.
Two years ago I converted my two main bikes to HID with kits from DDMTuming. The H4 hi/Lows are great. The shield makes the low pattern perfect and not blinding to oncoming traffic, yet the high gives me much more range. It went from about 9 seconds ahead at 45MPH, to about 18 seconds ahead.
I have always run driving lights for daytime conspicuity and to help at night. On one bike, I run cheap 35 watt spots (weak alternator). These work fine for daytime conspicuity but were not much help at night for distance even though they are spot lights. On the other bike I had 55 watt flood lights. Those also worked well for daytime conspicuity, but because of the broad pattern, did little for nighttime distance.
I have been putting off converting to LED auxiliary lights for two reasons. One, they are too bright to just leave on during the day, so I need a dimmer for them. And two, they have been stupid expensive.
Well, I had been working on a dimmer, one that would run them at a low intensity when other traffic is around, and would automatically crank them to full blast when I go to high beam. I just completed the design and build for that, so I ordered some LED lights.
I ordered these a couple of weeks ago for the bike with the flood lamps:
27 watt with a 30 degree spot pattern. The reality is that it measures closer to 21 watts. I ran a 4 hour test with no air movement, and it does not over heat. The pattern is exactly what I want, a fairly bright spot with what looks like a bit more then 30 degrees, and enough light scatter to cover the sides of the road. They work with my home brewed dimmer and I'm happy with the results. As for reliability, that will take a year to find out. The thing is built like a rock though. And I can't see any way for water to get in.
I wanted something significantly smaller for the other bike. Not a lot of good mounting options on it. So when I saw these, I ordered them (in the white LED version). Yes, the mounting bracket can be removed. That actually run at about 8 watts, not 15 as claimed. But then, at 8 watts for about 1 hour, they get very hot if there is no air movement, so I'm not sure much more wattage would be a good idea in that small package anyway. They are built somewhat poorly, but then for $23 I had low expectations. What is a bit of a problem though is that they are a VERY narrow spot. Much narrower then the 30 degrees on the other lights that I got. I haven't installed them permanently yet, as I need to build another dimmer, but the pencil thin beam will reach WAY out, if properly aligned. I may put a slightly frosted cover over it to scatter some light, or not. They also don't have enough water protection. Water can enter into the housing around the bolt easily, and not get out. So I could envision a housing full of water. The electronics has sealant on it, but I wouldn't want it to float in water as it is now designed. If you get these, plan to spend time water proofing it, or expect a short life.
I'll report again after a few months.