No. We do not have an export for content in the CMS as you stipulate.
Is there a recommended usage for Portal in enterprise production then?
With regards to the CMS only, I would rely on sql exports, but also make sure to copy over /data/portal directory if you're using a repository.xml different from the one in portal sar, or if you're storing ANYTHING in the FileSystem. Otherwise, you should not have to.
With webdav, it may prove easier to handle export/import, but I have yet to map the scope of that project out for 2.4.