I've been working with it for a few weeks. Developer but no gamedev background. I love it. Very easy, documentation is extensive, good support on the forums. I will agree with others in this thread who've said they don't like GDScript. For me it's not necessarily a problem with the language (although it's not immediately clear how script execution works - each script is attached to a tree node), but rather that it's another thing to learn. Given that, I've used custom modules (module compiled into engine) and GDExtension (module compiled as a shared library). GDExtension is what I wanted, and I can write a game in C++, and have it build quickly.