I've been meaning to buy one of these books for a while now, are they a pretty good source?
Several of my co-workers really enjoy them as reference. They say that it's a decent book to learn with, but it's more geared towards best practices with Django. So it can definitely explain some of the common pitfalls of developing Django applications.
It's an excellent reference for best (and common) practices, but I wouldn't recommend it so much as a learning tool. The 1.11 version weighs in at 549 pages and covers everything from installation and dev environments to security and continuous integrations. It's quite thorough and obvious the authors are well-versed in Django development. Highly recommeded.