Does Unreal Engine work well with large scale users and MMOs?

Unreal Engine 4 is designed to create small, fully-functional projects right out of the box. Since an MMO is a literal culmination of every extreme in game design, one might, quite understandably, balk at the idea of using UE4 for such a project. Fortunately, UE4 is easily modified at a source code level to allow for custom or extensive divergences from the default, small project functionality. We have identified what we need to change – most notably, the network communication and level loading code – in order to get the gaming experience that is expected of a modern MMO.