Working my way though the list on program-transformation.org, and checking references (publications, manuals, available downloads) for the systems,

seems to suggest that "reasonably mature" systems might include ASF+SDF, DMS, Elegant, FermaT, Stratego/XT and TXL, but I'm sure there are more.

I think you can add Tom (http://tom.loria.fr) to your list.

It is not as "high level" as ASF+SDF or Stratego for example. On the other side, it allows you to develop a Java application, using associative pattern matching and traversal-strategies.