We stayed for one night in September and were quite happy with the choice.
The hotel is indeed basic - yet the room was clean and not very noisy.
The breakfast isn't great - but the hotel is right in Sienna with plenty of bars and restaurants around it. So we just went out and had espressos and brioche elsewhere.
Overall: Good place to stay and start exploring Sienna (which btw is an amazingly beautiful city).

I booked the hotel via expedia for 85€/night - and was shocked when I arrived. The first room I was shown was a tiny gloomy room next to a huge noisy restaurant kitchen air-condition. Impossible to sleep there. When I asked for a calmer room, I was sent to the third floor (no lift) into a room that looked like a prison cell. The only window was placed in the hight of 2,5m in a niche. I felt like the Duke of Montecristo. Unfortunately, there was no WIFI which brought me to room no. 3. Noisy as well but at least with WIFI.

Needless to mention that all of these changes where accompanied by extremely odd discussions. I was told, I didn't know how to use an internet-connection - before another member of the staff admitted that the antenna for the third floor was missing. I was told that the extreme noise is what you find in a city (I live in Barcelona which is several times the size of Siena) The staff made no effort to hide that they where extremely molested by me.

When only an hour after my arrival, I said I would prefer to move to another hotel because obviously, none of the things I paid for - the WIFI connection, a nice, clean room - was offered, all I was said was, that the amount was charged already and that I could go but had to pay.

It was only the top of the list that later I found out, that on the Albergo's website the price of a single room was 40€, the one of a double room single use was 50€. I was shamelessly charged almost double as much - and no, there was no holiday, festival or whatsoever. They just did it because they could. STAY AWAY!

When we first opened the door to our room, the smell of disinfectant is so strong. The room was clean and they provided electric fan. The staffs were courteous as well. One thing I did not like was the bathroom. Curtain separates the shower from the rest and everytime we bathe, half the floor gets wet from the water in the shower. We were in room #3.

A two star hotel with no air conditioned, just a ceiling fan, but it is cool enough. The only thing is that it is slightly noisy outside if you were to open the windows in the room. And in addition, we had to carry our luggage up 2 levels and realised that there was a lift which permission is needed from the hotel staff.
For location, we boarded a bus from Florence and alighted at the bus terminal in Siena. We couldn't figure out our way initially and we decided to follow our instinct by turning left & we managed to see a sign that indicated 'Cannon'Oro'. And we walked straight and saw the hotel. But it is about 10 mins walk to the Duomo.
Free Wifi was really weak from the room & walkway. We had to use the wifi at the hotel lobby. Hotel staff was friendly.
Given the location, and for the budget of SGD 70.00 for two nights, there was nothing to fuss about.
Breakfast was not fantastic but it was free. Overall, will return to stay in this hotel again.