I finally received the bulbs in the mail yesterday so I could finish up the lighting upgrades on my '92 Miata. I built my own 12g relay harness and already had a pair of extremely nice used Z-Beams. I'd had the Z-beams in the car with a pair of standard wattage Hella bulbs before but no harness so they weren't running at full voltage. I'm really impressed with the X-Treme Vision bulbs running at full voltage; they have a cleaner beam pattern and are just about as bright as a pair of Hella 80/100 watt bulbs I had in a previous car with Z-Beams. Before with the 55/60w Hella bulbs and stock wiring I was thinking about adding a pair of driving lamps for better distance visibility on high beam, but they won't be needed now. I had originally thought about upgrading to JW Speaker LED's but I'll stick with these, I'm not sure that LED's would have as good of a beam pattern.