It can be argued that the best tank is the one that destroys the enemy. Or, depending on your point of view, it's the one that isn't shooting at you.
But otherwise, choosing the top tank is always a nightmare of technical and historical analysis. There are so many variables, and so many experts and history buffs that will argue those variables to the death. Yet into the fray steps "Armored Champions: The Top Tanks of World War II", written by Steven Zaloga, a defense analyst and well-regarded writer on World War II armored warfare.
So let's cut to the chase. What's the best tank of World War II?