I couldn't get any pics that show a difference between the colors, the pics were washed out by the sun behind the truck. 4500K is a nice pure white compared to the 5000K, much better looking IMO. If you don't want any blue then get 4500K. If you get 55W then 5000K will be white. The higher wattage makes the light more white than 35W

 

I have three sets of DDMs now, only have gotten slims.

 

Use normal ballasts where possible- the slim ballasts have heat dispersion problems and a higher failure (and inconsistency) rate than the fat ballasts.