@SavageEh, it depends on which writer, and what they're writing. For example: Ward butchered the Space Marines, but as a Dark Elf player from WHFB, I quite enjoyed his Dark Elf rulebook fluff.
Abnett
@Hank
Rising is good, it's a shame that Graham McNeil (who can do good HH books, see Fulgrim, Thousand Sons and Mechanicus) botched the corruption of Horus so badly in the following book and the characters were almost unrecognisable in the third book, by Ben Counter.
@Savage@Hank A Primarch's work is never done...