We had a great time staying at Villa Luna. It's an old house in traditional Tuscan style, very homey and cozy. The location is great, just outside of central Siena. We walked in every day for dinner and in case you prefer to go by car a cab wouldn't cost you much. Alessia was a dream to deal with, extremely helpful and flexible. We had a slight problem with the pool one day and she sent someone right away.
The only thing to be aware of is that the villas are not very private, you'll share yard/patio with the other villa and the pool is shared between the villas and the apartments (which makes it a bit crowded at times). The pool was also a bit dirty at times, with leaves and bugs blowing/falling in, but not a major problem. Overall we loved our stay and can really recommend this beautiful house to others wanting to explore Tuscany.