I mostly work with gdc from GNU/Linux, and basically, everything that works with g++ works with gdc. More precisely, I use, on a daily basis: - vim + ctags (editor + symbol lookup) - gdb (debugger) - gcov (code coverage) - valgrind (mostly callgrind (call-graph) and massif (memory profiler)) - oprofile (cpu profiler)
Unfortunately there's no ccache equivalent yet, and I'm missing it.
For the Windows people, there's VisualD, which basically is the integration in Visual Studio. At this point, you have an IDE and a debugger (I don't know about code completion).
There's also a build-tool (with package-managing abilities), called "dub" ; that handles fetching and building external dependencies (in the vein of npm).
Someone should do a Language Server Protocol (http://langserver.org/) implementation for D - that's clearly the way forward. Right now this will give you VSCode, Eclipse and NeoVim, with regular Vim and Emacs on the way.
VSCode also has something similar for debugging (https://code.visualstudio.com/docs/extensionAPI/api-debuggin...), but it hasn't been standardized in a similar fashion (yet?).
Learning D for real is as involved as any other language, but what people remark first is the low mental overhead and how absurdly practical it is.
Advantages I see would be: fast to edit, compile, and run. Non-controversial syntax, focus on power, and the fact you kind of already know it.