We recently stayed as a group of 16 in this apartment and thought it was absolutely great.
I think the main draw has to be location. If you're a group looking to sample Lisbon nightlife it's right on the cusp of Barrio Alto, home to numerous bars, so really just a few steps on your front door and you're able to soak up the atmosphere, which is perfect when there are lots of people to keep together! that said we had no issue with noise or anything late at night, as, as said it's outside on the cusp rather than on the main streets. Its actually beautifully positioned next to a 'miradoro' with views across to alfama.
the apartment itself is to a good standard with modern large bathrooms and plenty of space in the living room, we felt really comfortable there.
Communication with the host was also really good, with easy exchanges over Whatsapp and flexibility over early check in.
The only thing to be aware of is there is no air con, so some of the bedrooms can get a bit hot.
would recommend!