Used Chef before. In current gig, it's just me managing stuff. I picked Ansible over Chef and Puppet cause it's low(no) barrier to entry and simplicity. Also ability to ad-hoc commands means I didn't have to use another tool for that.

In the 1year since, Ansible has exploded in capability. It isn't quite as low barrier anymore (more to config language) but still gobs lower than others. While adding much sophistication.

I wouldn't even consider Puppet or Chef anymore. Salt or Ansible. Although, Python guy, so biased more than a little.