It may not be a step function improvement but the difference is still night and day: Dreading one more line of C++ versus looking forward to many fun lines of D.

I mean... Modules versus header files, 13 times faster compilation, introspection, unittest, etc. etc. etc. Okay, it's more like death by a thousand cuts but once you produce with D, you can't even touch C++ anymore. I am in that state...