It is a complete and utter pain for setting up and managing development environments.
I've been running a separate Linux box for 7 years as a development server - preconfigured, new virtual host, get working. It's a pain when per-project technology is needed and I want to find something better.
Vagrant is hip, so I've used that for the last 3 gigs. Getting the box functioning well, working round issues has cut my productivity by ~15% and doesn't seem to be decreasing with experience.
