The location is great, transport connection is very easy. I bought a 24-hour transport ticket in the metro and that is handy because if you are walking around the river you could just jump on the tram to get you back up. The flat a bit of a walk from the metro if you have bulky luggage, and be ready to climb the stairs all the way up (but I have to say for me it was easier than I expected from the description).
The host, Alex, was fast and easy to communicate with. The flat was clean, kitchen well equipped. I also saw various useful equipment in the flat - I didn't need it, but some might find it useful: ventilators, heaters, hair fan, all kinds of useful stuff. The view from the kitchen balcony is as fantastic as in the picture. Morning drink looking over the roofs with the birds singing is the experience you might want to go for.
I found the sleeping room itself a bit on the small and spartan side. I didn't understand from the photos that the window in the sleeping room opens into a ventilation shaft of sorts (or like an extra-small patio) together with all the other sleeping room windows of several storeys down. So the beautiful view that is in the ad is only from the shared places: from the kitchen balcony, or if one looks out from the living room window. For me that did not matter, as I used this place just for sleeping. But if you plan to "live" in the flat - be prepared to spend most of your time in the shared places: salon and kitchen, or otherwise stay in the small-ish and dark-ish room.
For me check-out at 11 was inconveniently early as my flight was in the evening. I could have left the luggage in the flat (there is a storage place for that, and Alex explained how to use it). But in the end I found another storage at the metro Maritim Moniz - the parking lot under the square has a luggage locker and it was quick and easy (and avoided climbing up and down). If you choose to use this kind of storage, bear in mind that the locker machines there only take coins (no credit cards) so come with enough coins to get your luggage.