I installed a pair of Hella 500's today, in front of my Yakima LoadWarrior. They're okay. Honestly, I was expecting them to be much brighter than they actually are. My buddy has a basic pair of KC Daylighters and they seem to be much brighter. I think two look lonely on the rack, so I was considering a 2nd pair (four across) for asthetic purposes... but due to the lack of brightness, perhaps the extra pair will bring the lighting performance closer to my expectations. On a side note, when purchasing the lights I also purchased a switch that suited my fancy and a 15A relay... The guy at the counter told me I would not need a relay and that the switch was enough... I hope he doesn't actually modify his own vehicle.