It depends on what you're looking for by "best color".
If you want to have HID lights for increased visibility (performance), stick with 3,000k-4,300k which has the highest lumen output.
If you want it for color (or looks), you can go with higher temperatures but the lumen output (visibility) will be sacrificed the higher the temperature.
Depending on your level of mechanical skill, you may be able to install the kit yourself. If you buy it local, they should be able to install it for you for a fee.
Aaron