> it's a different system from the server, lots of tricks are needed to make it work invisibly (either with a VM or a lighter equivalent)

I used to use Linux for this reason, but it's no longer a factor in my opinion.

Ideally your development environment should mirror the production environment, and just saying "the server is running Ubuntu Server 14.04LTS and I'm running Ubuntu 14.04LTS" is a pretty lazy and incomplete way of half-achieving that goal. What about your nginx config? What about your permissions? What about your PostgreSQL version?

Whether you run Mac or Linux, you're still forced to solve that problem, and the best tools to do it are all available and work great on a Mac. Vagrant is relatively painless and works really well.