Easily the best git GUI on Windows that I've tried.

I find SourceTree to be very slow and heavy.

If I need to use a GUI then I find the built-in Gitk and GitGui more than adequate. They're not pretty, of course, but they do the job just fine.

Yeah, SourceTree is easy to use and the latest release looks great. Although GitHub for Windows got me started with git, I much prefer SourceTree when I need a GUI (as a git nube).