We really loved the apartment. It is located in the heart of the city, only ten minutes walk to the next Vaporetto stop (perfect distance with small children), and ten minutes to Piazzale Roma (with its huge parking garage San Marco).
The apartment itself was beautiful - even better than in the pictures. Well equipped kitchen, very nice bathroom, very comfortable beds. There even was a small garden.
The communication with the owners was easy and they gave us lots of tipps to do in Venice.