We just installed LifeRay and Alfresco. Using the CMIS hook, we put documents from LifeRay into Alfresco. Though that works, we're quite disappointed.The way the files are stored in Alfresco make them unusable from Alfresco (we perhaps could live with the strange way this all is organized, but the fact the files are renamed and stripped from their original extension, that's just awful).
The other way around doesn't work either: when storing files with Alfresco in the LifeRay repository, LifeRay can't handle the file.
From an architectural point of view I can see why this was done, but this is something one cannot explain to end-users. They expect a more tight integration (and quite frankly, so would I).