Which is better: TAILS or Whonix?(self)
I recommend you take a look at both, since their approach is different and what 'is best' depends on the context.
Care to elaborate?
I can't do better than the homepages of the projects.
TAILS is (best) without persistence from a USB: "Tails is a live operating system that you can start on almost any computer from a USB stick or a DVD. "
Whonix is something you run in your OS: "Whonix ™ isn't a program like most of your applications. It's a full operating system that runs inside your current one. Select which operating system your computer is running."