4500 might have some yellow in it. I think I was origninally going to get the 55 watt ballasts, which would have adjusted the color a little; but I'm really happy with them.

Compared to all the 6000k lights that you see coming down the road, these look way better as there's a lot more white in it. It's up to you. You can always buy more bulbs if you aren't happy with em. *shrug*