This new NavMesh work basically saved my ass. The game I'm working on now requires dynamic updates so to have that ability in 5.6 is a life-saver. I do have one concern, though. Correct me if I'm wrong. In the old NavMesh system, you bake a mesh and then each NavMeshAgent can specify its own size for collision purposes. NavMeshSurfaces can only be baked for one agent at a time so now if I want to have different agent sizes, I need one NavMeshSurface per agent type. For most games, you'll have a different size for almost every unit type. If I want to update the mesh real time, this update time now basically scales linearly with my model count. This strikes me as a performance problem as well as a bit of a logistics mess as I'll have to have one NavMeshSurface component on my terrain for each agent.