I've read both of them or rather I have listened to Ancestor and read The Dip. I recommend them both if you haven't yet.
Be warned though. I firmly believe that reading The Dip will f**k up your situation in life because it will get your noodle going and questioning a lot of things. That could be a good thing or it could send you into a weekend of questioning like it did for me. Full book review coming shortly on Managing the Gray.