In reply to dondon:
thanks all for the info.
also found this PDF which is very useful:
http://deandar.com/pdf/post/dossier-ferratas-serrania.pdf
Did tajo de ronda 1 and tajo de ronda 2.
Tajo de ronda 2 is very easy with not much exposure. great for beginners.
Tajo de ronda 1 was steep and slightly difficult due to the rain.. put my girl friend off via ferrata's so unfortunaly didnt get chance to visit the others.
there are many other via ferratas in the ronda gorge not in the PDF. the 2 in the PDF are the only 2 with cables running from the ground up.
I checked one of the un-cabled ones out, but the rungs just ended after about 10m.