It's not performance --- it's reduced setup overhead. The main upside of something like Heroku is that if you want to get something up quickly, you don't have

It's not performance --- it's reduced setup overhead. The main upside of something like Heroku is that if you want to get something up quickly, you don't have to bother configuring a VPS for it; run three shell commands[1], and there's your app, running on the public internet. The main downside of something like heroku is that if you want to do something that would require custom config on a VPS (e.g., installing some oddball software package), you can't. There are also restrictions on what directories you can write to, and so forth, and some fairly common gems require workarounds to deal with them. But enough people find it a net win that they've had, I believe, the largest YC exit to date. [1] Walkthrough here: http://docs.heroku.com/quickstart http://docs.heroku.com/quickstart