From this site
http://ghonis2.ho8.com/rebelmod.html I noticed some before and after photos that are a little dis-heartening. The before shots look as you'd expect, obviously the after has a red shift, but the after with custom WB still doesn't look right. The sky is still blown out, the shadows don't look right, and the whole WB still is off to my eyes.
Does anyone have better examples? Not sure if this is typical results across the board or if the person who posted that didn't quite spend enough time with WB and maybe the sky had more clouds in the second and third shots making the sky lighter.