C++ VS blueprints - Blueprint - Unreal Engine Forums. In this post and I read this somewhere too; blueprints are ten times slower then C++. Looks like It is an average performance loss. This is the first problem when you are using blueprints with large scale projects. Another and the most important thing is when you are dealing with large scale project, you must implement some inordinary data structures, functions…etc. Implementing them with blueprints obviously not a good idea. As an example it is not a good idea to program Skyrim or large open world maps or MMO’s using only blueprints…
I think using %10 c++ (specialy for critical areas) %90 blueprints will be worked except large projects.