[CarlG]

I have been using the Quartz Halogen reflectors & bulbs (9007) for 5+ years. And, no, there is no focus adjustment, just headlight aim as in your modern cars. I have had no problem at all with the Quartz Halogen set up. I have, however just changed out the bulbs in favor of LEDs. That was pretty much a "plug & play" exercise. Time will tell if they work as well as advertised. I mainly did the change to decrease the current draw since state law requires headlights on at all times on state highways. They certainly do cast a brighter and whiter beam than the Quartz Halogen bulbs did.