Things you can do in RoR you can't do in PHP: - Search through its documentation to find it's badly or incorrectly documented - Use crappy gems such as Devise which give you hours and hours of fun Googling how to customize it - Wait for 30 seconds for your development server to start

Have used Rails for 2 years, PHP for 5 years and Django for 3 years. My advise: go for Django. Awesome documentation, a fast booting development server and Python libraries are documented really well. All batteries included and it beats RoR performance easily.