Bingo. It's really annoying that I can't use tuple/dict (un)packing without it complaining, let alone that if I have a class which is too big, too small, or does too much/too little, it throws a fit. Worse, it doesn't understand zope.interface and gets quite irate when confronted with interface-heavy code.

I'm usually working in Twisted or Django, and it's so very unfun to try to get pychecker/pylint to be okay with those libraries. I'd rather have pyflakes.