They are fine in the evening but I'm not usually one for white dress shirts for day wear. That's partly because I agree with Hardy Amies, who wrote that they are a bit naff compared to blue or cream, and partly because they seem to wash all the color from my face. But there's one exception, and that's when I have a sun tan.
A tan seems to bring out the best in a white shirt, which is a good thing as white seems to coordinate especially well with the lighter colored suits of summer. Not to mention my favorite summer necktie (pictured), a blue so light that it loses its impact on anything but a white background. Time to order white linen from my shirtmaker.