Great place to stay, recommended and we would stay there again.
Very conveniently located near the Rialto- which is very busy- but a block away from the Grand Canal itself, so was nice and quiet.
The core of Venice is pretty small and you can easily get to most places on foot or by the fantastic water bus system (which operates a bit like a subway system but on water) from the flat. The Rialto is 2 min away and San Marco is 12 min on foot.
Flat itself was a decent size for 6 people - one double bed for adults, two twin beds and then a double sofa bed in the living room. Thankfully the flat had good air conditioning which was a true blessing as it was around 35 during the days we were there.