DigSig & XML Experience

Is there a body of actual hands-on deployed-in-the-real-world  
experience out there with XML DigSig & XML Encryption?  I don't know  
of much, would like to hear of any.  Pointers appreciated.

The specs: http://www.w3.org/TR/xmldsig-core/
            http://www.w3.org/TR/xmlenc-core/

  --Tim