These bulbs are a huge difference in brightness. I put them in a 2008 Ford Mustang. Adjusting the rotation was a bit frustrating, but once I got everything lined up they work great. I was afraid the high beams weren't going to be noticeable, but they are. I just installed them today and I drove around for about half an hour with no problems. They didn't flicker and they seem like they were factory installed. The passenger side was a pain to install. The bulb was having difficulty inserting into the headlight assembly. I really had to finagle it and it finally locked into place. There were no instructions, but they were self explanatory. There are two itty bitty screws that you adjust with a tiny Allen wrench. Be careful adjusting them. One of my screws fell out and I lost it. Once the screws are removed you can then rotate the bulb to line them. They don't turn easy, though. Overall I'm satisfied.
