When we told our driver where we were staying he said, "Wow, you're in the middle of everything!" And right he was.
Location, location, location. If you like to eat and explore, you couldn't ask for a better jumping point. We only had a short stay and were tempted to spend our entire time at the Time Out Market next door, but glad we ventured out.
Check-in was easy (once I read the instructions Patricia and Vasco thoughtfully provided right in the Airbnb app) and the other reviewers were correct - clean, modern, safe building with very helpful and nice security at front desk.
As for noise - yes, slightly. Not overly and, unless you're very sensitive, not really an issue. You have to remember you're staying in a hip location with a lot of young people and a food paradise that is only closed from 2am - 4am, 365 days a year, within steps.
Would stay again for the city portion of my next trip to Lisbon and would recommend to fun friends. To the old and stodgy, not so much.