My friend ownes a lighting company and just got thos in. The day i got my xmr he put one in the headlight to see if it would work, in broad daylight it shined against the truck from about 8 feet away like it was dark out. They are wicked bright...... But.... I didnt leave them in there because i thought the exact same thing that heat sink will get full of crap im the mud or thel will get cought on somthing n ripped off. It will be hard to find a led headlamp thats bright with out a heat sink of somesort. Leds get hot with out cooling they burn out quick. How much did you find those lights for.