My partner and I stayed in Alessandro's apartment for 4 nights at the end of July. Great little apartment, very practical, and there is a washing machine and dryer in the building that is coin operated, for guests to use.
We easily got the bus from Heathrow airport to Victoria station, and then walked to the apartment. Check in and check out was extremely easy. The apartment was in a great location, close to 2 tube stations and close to numerous restaurants, supermarkets, and anything else you may need.
Alessandro provided a bottle of wine, a loaf of bread, some juice, a beer, and a bottle of milk in the fridge, which was a very nice touch. We cooked dinners and had breakfast a few times during our stay, so it was very convenient for us to already have some wine and bread! There was also some tea bags and a few snacks in the cupboard.
The only downfall at the time was no air-conditioning (we were in London during a random heatwave and there was a bit of airflow but we still found it quite warm in the room) and, dare I say it, a TV (purely because we were in town when the royal baby was born and it would have been nice to be able to see some of the coverage about it given we were there!). But these are just minor details that wouldn't have been an issue staying there at just about any other time, and given we didn't spent too much time in the room anyway it wasn't really a problem for us.
We would love to stay in the apartment again next time we are in London, and I would happily recommend it to anyone considering staying in one of Alessandro's properties!