On a personal note, out of the box, I much prefer bzr, it's easier to use and the default workflow is optimized for a project with a relatively small number of regular contributors, like calibre.
However, git, after some customization, scripts/aliases and so on, works just as well. You do have to put in much more upfront time learning and customizing it, but then, given that I use vim, I can hardly complain about that
