We stayed at Ca' San Vio for two weeks, and I would definitely return. The neighborhood is extremely convenient: 2 minutes from the Guggenheim Museum and the Academia Bridge, and five minutes from the Zattere airport shuttle boat stop. It's about 10 minutes from San Marco Square, but without all of the noise and congestion.
The room was small, but very comfortable. The walls are covered in silk fabric, which added to the quiet aura of the pensione. Because the Ca' is a few blocks from the Grand Canal, the neighborhood is more residential and very quiet. The bathroom was immaculate, and while not luxurious, it was certainly adequate.
The continental breakfast was delivered to our room, and the food was fresh and tasty. There's also WiFi access in the room for a very nominal fee. And the Ca' is close to lots of restaurants and cafes.
During our stay, some of our relatives joined us, and they were placed in the room next door. We were able to keep the doors open and visit back and forth, whcih added to the fun of our stay.
We paid a bit less than expected, and Marco gave us a Murano glass cheese cutter as a going away present. Ca' San Vio is reasonable, convenient, clean, and friendly. We were very pleased, and I'm sure we'll stay there on our next trip to Venice.