I usually use pep8 and pyflakes directly from the command line. As Zygmut said, pflake8 is a handy tool (if I'm not wrong it runs pep8 and pyflakes).
Before a commit I run the files also under pylint, but it is a manual process since it can report lots of warnings that one can actually ignore.
I personally prefer to stick with distro provided tools, without having to go through pip or easy_install, but I guess this will become a problem since we are all using different distros with their own package versions.
Probably we should suggest a minimum version at least for PEP8 and provide a simple pep8 config file to share (we witnessed difference in PEP8 reports between Ubuntu 12.04, 12.10 and 13.04). For the other tools (pyflakes, pylint...) one should be able to use whatever version they have available: we will still go through code reviews and the errors those tools usually report can also be checked at that time.
I'm more keen on having strict PEP8 checking so that the code will (almost) have the same style, and will be a little bit easier to read. I would stick to the 79 chars line length, plus all the "default" PEP8 settings (multiple spaces, no space between operators...).
Ciao.
-- Milo Casagrande | Automation Engineer Linaro.org <www.linaro.org> │ Open source software for ARM SoCs