We have just returned from a lovely 6 nights in Florence. We (My wife, myself and our 18 month old son) really enjoyed the apartment. It was well located - within 20 minutes you could walk anywhere in central Florence and many attractions are much closer. Kitchen has most things you would need and was clean. Supermarket close by. Some great bars locally for nightlife.
From a family point of view location was excellent as there were 3 childrens playgrounds within easy walk.
The only 2 things worth mentioning as a slight negative is that one of the bedrooms (the smaller one) doesn't have a fan and as there is no aircon in the apartment it can get very hot. The other thing is that there was minimal cleaning equipment provided - cloths, washing liquid, teatowels etc - these basics are needed and had to be brought.
I would recommend it and I would return.