[jackfraser]

I've worked with GoCD in production a bit. It's a bit of a beast to keep running, the UI is very strange, but the pipelines are extremely powerful and make for good separation of stages. I found it awkward to configure jobs, though, and the documentation is not excellent. There's also a much smaller plugin ecosystem than with Jenkins. We ended up having a guy spend a good lot of his time, nearing 50% some weeks, just keeping GoCD happy for a couple hundred devs.

Overall, I would choose Jenkins first unless you know there's something GoCD can handle significantly better.