How close are development webservers to production webservers?
I develop with django. The production server we have is remote, so it's a pain to be using it for development. Thus, at first, I created a vm and tried to match as closely as I could the environment of the prod server. At some point that vm got hosed (due to an unrelated incident). I took stock of the situation at that time and realized there really was no good reason to be using a customized vm for development. Since the resources available to the app weren't the same as the prod server, it was no good for timing queries anyway (in an absolute sense).
That said, I now use django's built in dev server with sqlite for development, and apache/wsgi and postgresql for production. As long as the python dependencies are met on both sides, it's 100% compatible. The only potential problem would be writing raw sql instead of using the orm.
Most python frameworks will have a development webserver of some kind that will have a warning that it isn't for use as production servers.  How much different do they tend to be from their production equivalents?
I haven't quite decided which framework to go with, much less what production server to use, so it's kinda difficult for me to pin this down to a "compare development server x to production server y."  So with that said, let me make the question a little bit more precise:  In your past experience with a python framework, how much time did you have to spend getting your application up and running with a production system once its been developed on a development server?  Or did you skip the development server and develop your app on a server that's more like what you will use in production?