I like pytest for the ergonomics of its static setup/teardown/fixtures (plus not having to stuff everything into a unittest.TestCase). Unless you mean using generated input in those bits? In which case yeah, not ideal. At $dayjob we do some chonky processing; generating new input for each property we're testing is just barely ok right now, but that's probably not going to hold for very long.

[1] https://github.com/pytest-dev/pytest-subtests