The apartment itself was quite nice! 3 bedrooms plus an office -- with a large living room / dining room / kitchen. It was a comfortable place to spend half of our time working and half vacationing. Nothing to complain about with the wifi: speed or coverage.
The downsides were mostly with respect to the rest of the experience. The elevator went out multiple times during our 5 night stay for significant periods of time -- being on the 6th floor (which is really closer to 9-11 sets of stairs with double-height apartments) this was quite inconvenient to move bags down / leave / return. One time one of us was stuck in the elevator for approximately 20 minutes. The app that was used to provide us access to the smart lock entrance to the apartment was a little buggy -- and, despite asking multiple people whose contact info we were given, we never received a response with information to set up an account on more than one phone. The only real downside with the apartment itself was that it seemed the condenser on the dryer seemed to have never been cleaned -- there were thick layers of lint that made it not work. Once we discovered this to be the issue, we were easily able to solve it -- but it made clear that this was not a place that anyone actually lived in.