There was absolutely nothing to dislike.
We cannot say enough nice about Fra I Sassi. We were lost trying to find it, but the gracious host, Domenico, came and found us to lead us to it. He arranged parking for our car, helped with our luggage -- all with a very wonderful smile. Staying in the Sassi was a unique and wonderful experience. The room was large, comfortable, immaculately clean, with good WiFi. The bathroom (once part of a cave) was enormous with wonderful twin sinks and a huge, easy to use shower. Breakfast was delicious and abundant. Domenico gave us great recommendations for restaurants and arranged a superb guide (Silvio) for an afternoon tour. Without doubt, this was our favorite place to stay during our month long time in Italy. A stay here is a must for any tourist in Matera.