We staid for ten days at this beutiful place in the heart of Tuscany and could have staid for several more. The facilities is excellent and the host (Alberto) is very very nice and helpful.
Except of spending time at the pool we made several trips to different places around Tuscany. Some of the places we visited were Firenze, Siena, Saturnia, Montalcino, Montepuliciano, San Gimignano.

We can really reommend this place for others.

The Rodman´s

We stayed two nights, and wish we could have stayed for the week. What a wonderful place. We were greeted on arrival by a friendly face (despite our 1.30am arrival). The apartment was spotlessly clean, and fitted out with everything we needed. The place is set in beautiful surroundings with a vineyard up the hill, and mature trees around. The pool was a good size, with plenty of room for people to lie around without feeling cramped. It was also lovely and quiet (except for the croaking frogs and birdsong - which was absolutely glorious to hear when you've come to escape London for the weekend).

The owner was also very obliging, despite our language barriers, and showed us where to park, shop, and eat in the town. And he allowed us to stay by the pool beyond the check-out time on the last day, which was a nice little bonus.

While it's within walking distance to Castel, we drove up in 5 mins, and got our supplies from the local co-op, and visited the local bakery.

We're now trying to figure out how soon we can go back there!

Terre Gialle is a beautifully renovated building with very nice, well maintained grounds. The host was very kind and welcoming, and clearly no expense was spared in the renovation as the quality is excellent. It is extremely peaceful and picturesque. It was about a 3 hour drive from Rome (we rented a car at Termini Station). A great weekend getaway. If driving from Rome, don't bother with the coastal route - it is not scenic and was much slower.
Terre Gialle is close to numerous ancient hilltop cities which were fun to explore. Archidosso and Montelaterone were charming. Castel del Piano has everything you need (2 grocery stores, bakeries, etc.) and several charming squares with fountains and benches. Mount Amiata is a nice drive with pleasant restaurants at the top (still had snow in late April!).
Note that there was no TV, microwave, toaster, clothes washer, iron, etc. It's very minimalist and the room was not particularly comfortable for lounging, but that forced us to get out in the fresh air, which was good. We had read reviews which warned us that no food is available on site, so we stopped in Castel del Piano on our way and stocked up at the grocery. A highchair and cot were provided, which was very nice.
The only con: the steps to the bedroom loft were very steep and seemed a bit slippery, and I was nervous carrying my infant up and down, and worried about my 2-year old falling down. In the end, nothing bad happened and all was well. We put the 2-year old in the cot to ensure he wouldn't fall down the steps in the night.