If you're planning to stay in Florence just for a day, I wouldn't recommend this place. However, if you're planning to stay more than 2 nights there I would recommend you to stay there for sure.
The policy of checking in only between 3pm to 8pm is kind of nonsense, specially because if you need to check-in after 8 for some reason, you'll need to pay 20€.
The place is amazingly clean, close to a supermarket and to the train station. The host was helpful giving us hints of must sees and places to go.
But the fact that we cannot leave our luggage there for a couple of hours after checking out bothered me a little bit.