Yup, 3 weeks in two years ('03 + '04). Crewed with friends on a Moorings boat out of Athens (Kalamaki) and two separate weeks from a Greek broker/charter firm 1 week out of Kalamaki & 1 out of Kos (one of 5 boats Cats & Monos).
very good Greek firm that does lots of biz with europeans + americans
http://www.egiali-yachting.gr/
Know that reputation has not slipped in recent years