Got to go with Space Wolves after reading Prospero Burns, that book really emphasises how odd they are.
It's great seeing so many Space Wolves. When I first got into the lore and gaming around 40k, it seemed like a lot more people preferred the Ultramarines. My how the times have changed.
Dark Angels, there is just something off about them since reading the Horus Heresy book. Lion El'Jonson seemed to sit on the fens abit. "A moment of Laxity spawns a lifetime of Heresy"