Ranked in these QuestionsQuestion Ranking
Pro Free and open-source
Released under the MIT license.
Pro Powerful autocompletion
Spyder's autocomplete features are made possible by a library called rope which gives Spyder powerful autocompletion.
Pro Graph plotting support
Spyder can plot graphs and provide the list of all variables.
Pro Has cross platform support - Linux, Mac, and even Windows
Spyder (formerly Pydee) has support for all of the major operating platforms - Linux, Mac, and even Windows.
Pro Relatively lightweight
Pro Helps you to use documentation
Pro Intuitive interface
Pro Enables to write consistent code
Pylint integration enables to check the code for PEP8 style guide and detect errors.
Pro Has support for Vim bindings via plugin support
Aside from being an open sourced, actively developed IDE, vim key-binding support is also available. If you remember Pydee - this is it, albeit with a new name.
Pro Good GitHub project
Pro Excellent variable explorer
Dynamic variable explorer with editor and visualizer
Pro Completely Python
Con Not beautiful
The default theme is not beautiful. And there are not many themes.
Con The documentation is poor when it comes to debugging
Not a lot of information about debugging is available in the documentation.
Con Consumes a lot of memory
If you're working with large data, especially arrays, another IDE should be considered as spyder uses at least 200-300Mb of memory.