As you probably know, we are in the process of designing a tool which will provide a way to migrate from Pulp 2 to Pulp 3, so we will ask you for feedback every now and then.
Export distributor  is used for generating ISO images which can contain one or more RPM or File (ISO plugin in Pulp 2 terms) repositories in it. This distributor is also used to export a repository into a specific directory on a filesystem.
Please, let us know if you use export_distributor:
0. Do you use Pulp directly or through Katello? This thread is more relevant for those who use Pulp directly.
1. What is the scale? E.g. "I use it for 10% of all my repositories, ~50 repositories."
2. Do you export into an ISO or to a directory? Or both?
3. Is it important that export_distributors and their configuration are migrated to Pulp3? E.g. "It would be nice-to-have, not critical, I export very few repositories."