I think it was more that the automated web testing part of Pylons wasn't particularly well integrated with SQLAlchemy. So (eg.) it's basically impossible (AFAICT) to populate the database with preexisting data and then directly call the controllers, since when you commit the data in your controller, you can't access the database afterwards when you get back to your controller. Instead, you get lots of odd tracebacks - things like "Instance <Foo at 0x103779f90> is not bound to a Session". It also means that you can't do rollback type testing - you have to stick different data in, or blow it all away and recreate it manually.

Django on the other hand, has fixtures, which you can create from your existing database, and use rollbacks, so they're really fast. Combine that with the test client, and I can just write my test cases and forget about setting stuff up. People often go on about Django's admin interface, but I find that the rest of the framework is written to the same sort of standard, so there are lots of hidden gems (like fixtures) just waiting for you to find them.