This is a compact and excellently located place to stay in Lisbon if you don't mind being right in the thick of parties and nightlife in the evening. There is a very busy bar right opposite the flat and it is quite overwhelming in the street during the weekend, but once you are up in the flat, with the windows closed, it is just a dull buzz.
We stayed in February, the weather was lovely, but cool in the shade and in the evenings so we kept the windows closed, the apartment is quite cool but in the summer you may need the windows open, then the noise would be quite intense.
The location is great and we managed to see most of central/ downtown Lisbon, all in walking distance. There are plenty of great restaurants and bars in the Chiado district, just about 10 minutes walk down the hill towards the River.
The only issues we experienced were a very squeaky, creaky bed, and the fact that the cooker causes the electricity to cut out - we were only boiling a kettle, but if you plan to cook meals, this may be too much of an issue.
Jorge was an absolutely excellent host, he greeted us at midnight at the apartment, sat with us for about 30 minutes to show us around the flat, tell us how everything works (including where to find the fuse box), and give us lots of tips and information about the city. He was also available anytime for queries, fresh towels etc, although we never needed it as everything was fine.