Today I worked a bit on pas.plugins.ldap in order to get a new release of the underlying node.ext.ldap out. Since we are perfectionists this will be an 1.0alpha1 - but its really stable and already in production for a bunch of large installations with thousands of users.
pas.plugins.ldap itself is already very stable. I just checked for Plone 5. Test had one failure, some import changed from Plone 4.3 to 5.0. I fixed that https://travis-ci.org/collective/pas.plugins.ldap/branches A new release is pending, expect it in the next days.