User blog comment:Hockeyben/The new look - one year later/@comment-3279487-20111015161614/@comment-1401334-20111015230031

What do you mean by "the results it's not the same thing"? With CSS you could create the exact same appearance that you could get by using the theme designer (if you wanted). The only difference is that with CSS you have much greater control over your customizations, so you don't have to rely on Wikia's automatic color schemes.

In terms of customization ability, CSS trumps the theme designer.