I'm not so sure (given I spent quite some time learning Chef). With Chef I can deploy to a Vagrant VM running on my laptop, to a local server, to our VMs hosted

I'm not so sure (given I spent quite some time learning Chef). With Chef I can deploy to a Vagrant VM running on my laptop, to a local server, to our VMs hosted by another company, or to EC2. This is great for testing, and it gives some useful diversity. For example, the disk IO throughput on EC2 isn't great so we're considering deploying our data stores to some dedicated servers. We can use the same deployment process to manage these and our EC2 servers. This seems like a win.