I found this blog post where the author was trying to show the difference between these two. They both work but in different ways. If you click on the google translate link near the end you will see more examples and how bad effects in both can come out.
I'll give the author credit for simply showing and he doesn't appear to be picking one over the other. Normally when you see a subject like this it is the GIMP community trying to nay-say Photoshop. I think both did an admirable job in the first image.
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