I think it's a fantastic book - an absolute must-read.
I enjoyed A Thousand Splendid Suns as well, but it didn't quit soar to the same level.
Yes, the story is brutal, at times - this is not cheerful reading. But the book is well worth the read nevertheless. The writing is superb, and the author does a wonderful job at leading the reader towards understanding the settings, the mindset, the historical events.
I wouldn't recommend it to a kid, due to the sometimes disturbing themes, but nothing in there is the gory-sadistic brutality of a splatter movie/book. The violence, in this novel, has its place in the narrative.
Frankly, the more I think about it, the more I find it disturbing that a book of this level is being discounted or even criticized for one brutal scene. Are we entering a new phase of reader-driven-censorship? Do we want writers to tell us just fairy tales, to convince us that growing up in a war-torn country was all smiles and hugs?