I have never liked the user interfaces of either Eclipse or Pycharm, so it is hard to be impartial. Liclipse, for those unfamiliar with it, is an Eclispe based IDE, that is a successor to Pydev. Both are proprietary, but prices are reasonable. After trying them again I still do not like Eclipse or Liclipse, but I do see the appeal of Pycharm.
The reasons I dislike these still apply: they feel less responsive than the other IDEs I have tried, and the UI is not particularly comfortable.
Pycharm does have a lot to like as well. It does a lot to help: for example it will warn you about modules that are imported that are not in your current virtualenv. It has good autocompletion, call tips, a debugger on par with those in Wing and Komodo. It also makes helpful suggestions: for example. it spotted a call to set() that could be replaced with a set literal. It also classifies warnings as weak or strong, and tells you how many there are of each in a file.
On the other hand I still have the UI, it feels sluggish and it is a memory hog (600MB with a small project open). Given that other IDEs do what I want, I see no compelling reason to buy it.
Liclipse looks promising but us far weaker. Its auto-completion saw not good, and it seemed to have no particular strengths. Nothing in particular to recommend it as far as I am concerned.