8.x-1.x or 8.x-2.x

8.x-2.x uses the core entity reference field and the custom inline entity form module to provide the forms on the content edit page. This will display each field collection item in a row in a table for your field and allow you to edit one of them at a time.

8.x-1.x uses its own custom field display that allows all field collection items to be open at once on the content edit form, more similar to the interface in 7.x. It is closer to production ready.

Can this info go on the project page? Currently it is hard to tell which, if any, 8.x version is usable.

Am I ok to assume there will be an upgrade path from 1.x to 2.x?

Do you know how far away or what issues are blocking an alpha or beta release?
With Drupal 8 being so new it is easy to assume that a development version is not usable.

I think there will be an upgrade path to 2.x if it someday becomes the preferred version of the module.

There is already basic functionality and tests in place, so I don't think there is anything holding back an alpha release. I don't currently know any critical issues that would prevent a beta but it could probably benefit from some time in alpha first to see if anything comes up.

I have edited the project page and released an alpha version of 8.x-1.0.

Hope this helps.

Great, thanks