We stayed in the apartment for 10 days in August. Here are the positive features:

1) The apartment is large and well appointed -- dining area, sitting area, kitchen, large outdoor deck, large bedroom with bathroom next to it and large closet.
2) Centrally located to the major tourist attractions
3) Extremely quiet
4) Well air conditioned
5) Because it is on the fifth floor, it provides a good view of the immediate surroundings.
6) The outdoor terrace is extremely pleasant to use -- not exposed to the direct afternoon sun and very secluded from other decks in the immediate area.

Here are negatives:
1) Because it is centrally located to the major tourist attractions it is generally very busy from 10 in the morning to 9 at night. In some ways this could be regarded as a comment upon all of Venice! The cruise ships, of which there were about 5 in Venice when we were there, places a great burden upon the infrastructure of the city. This area near St. Marco is one of the busiest in Venice.
2) One generally has to use the stirs to access the apartment so one needs to be prepared to climb five stories of steep stairs. There is a chair lift, in which one person can sit, but it is very slow and unsuitable for regular use.
OVERALL:
The apartment more than met our expectations and so we were extremely pleased with it. It provided a very positive element to our visit to Venice. I would stay there again on my next trip.

One great thing and totally an accident was that it is just a few meters from a restaurant owned by a very famous chef where we made reservations for our first night. We did not realize how close we were as we could not get the exact location of the apartment before we arrived and could not add it to our off-line map - so we were very happy to learn we were so close when we arrived and turned on the GPS.

The restaurant is called
il Ridotto Restaurant
Castello 4509 - 30122 Venice
Campo SS. Fillippo e Giacomo
You need to make reservations before you go, so it is a very convenient place to go for your first night in Venice. We loved it.

Karen