Short review: The more communal style of this place won't be for everyone, but if you don't mind being around other travellers, this place is great.
Location: This BNB really added to our experience in Florence. It's almost directly across the street from the Mercato Centrale. When you step outside in the morning, you're instantly engulfed by the market's energy, and we loved this. About a 4 minutes' walk to San Lorenzo, 6 minutes to the Duomo- Very conveniently located. For domestic needs, it's right next to the Via Nazionale, which has a grocery store, 99 cent store, and coin-laundry.
Hosts: The hosts are wonderful! Very friendly, communicative, and obliging. Veronica's husband resolved all our transportation concerns, gave directions and made notes on our map, and gave a few wonderful suggestions (I still can't stop thinking about Nerbone's panino bollito). Perfectly fluent English, so no worries there.
The place: Beautiful! The room was wonderful- really great character. Everything felt very safe and secure. Off of the kitchen, there's a nice little terrace to enjoy morning coffee or evening wine. There are, I think, 4 rooms and 2 bathrooms, so you'll see other travellers and share a kitchen. This won't be to everyone's liking, but is, I should note, just as advertised. The steady air conditioning was very welcome during the Florentine summer. Wifi was good.
Overall, a really wonderful experience!