better to use unity terrain or plane prefab?

I created an infinite landscape using standard plane meshes, and I have seen the "coherent noise asset" uses standard terrain objects for a 2x1-tile infinite terrain dynamic platform, which is good because the terrain uses LOD etc, and it can change masses of vertices and normals of the mesh without stopping for a frame like it does with other procedural mesh in unity.

I don't know if it would take too much resources to use multiple terrain objects for example 4 of them for a 2 x 2 zone around the player, would there be pauses for calculations? would it have better performance and memory and textures? would it be more efficient than using plane prefabs? what would be the advantages and disadvantages?