Hey guys, I'm a bit of a geek for anything LED. I haven't had car headlights LED yet, but I've had hiking and biking LEDs for a while now and take interest in the tech behind the scenes. The input so far in this thread has been awesome, and my first car headlamp LED kits are en route right now.
When buying LED "stuff", please be aware that there are TONS of LED emitter types out there. There's an explosive development in this field, and new and better emitters are rapidly being put to market. This means there will always be heaps of cheap stuff that are yesterdays news.
The most common evolution of emitters, is that new versions are usually putting out more light per watt than the previous. Maybe not so important in cars, but for stuff you're going to carry - it matters.
Regardless - stay away from the LED bulbs that are stuffed with tons of emitters. This is really cheap stuff. Maybe they can do for a number plate light.
Be careful if you see someone claiming mad lumens... it's usually too good to be true. The china sellers are unfortunately worse than most in exaggerating. If they for a second thinks its going to boost the sales to claim 10.000 lumens from a bulb, thats what they will try to sell....
There are two commonly used emitters today, the XM-L2 and the MT-G2. The latter is a big larger than the first. the best XM-L2 emitter revision is named U3. The best MT-G2 emitter is the P0. The difference in output for the same wattage, is about doubled from the first MT-G2 emitter to P0, so it does matter.
It looks like the better bulbs now are the ones with MT-G2. Based on the great recommendations in this thread, I found some good resellers for my Euro H4 headlamps. I've ordered three kits today - two Cree 3200lm kits, one with external drivers, the other one without - as well as the vleds ultra, which is based on Philips Luxeon emitters. The vleds are on pre-order for another 3 weeks, but you get a $50 discount so it might be worth your while.
I'll be back to post the links in two days when I'm not such a rookie and have my two required posts done
