Best practices for configuration for staging environments

[Allexicus Kernikus]

In a department meeting we had a discussion on changing our methods on addressing staging environments.

Up to now we generated a deployable for each staging environment (e.g. DEV, QA, PROD). From now on we want to generate one deployable and load the configuration file at runtime.

Is that the right way to go? Does it really bring along additional flexibility?

Also, a good how to/best practices guide would be very much appreciated.

Thanks in advance! - LX