Me and my girlfriend spent a week in Vaggelis' studio. We had a wonderful time there. We haven't met Vaggelis in person, but we were greeted by his grandfather, who was very welcoming and friendly even if he doesn't speak english.
The location is perfect for those who enjoy a quiet and wild summer vacation, as it is located a bit distant from the two main villages (about 15') and is close to the best beaches you'll find in Serifos (Ganema and Vagia). I'll definitely come back again when in Serifos!