I stayed in Jo's place for 5 nights in November for a conference. The apartment is nice, cosy, it really has everything you need. Jo was very attentive and asked me several times how I was and if I needed anything. He also left some tips to enjoy the neighbourhood (Balboa Park and The Lion's Share would be my recommendations)
The location is fantastic, right in the middle of Gaslamp Quartet and very near the San Diego Convention Center. It was placed in the busiest street in Gaslamp (which worried me at first), but inside the building, you couldn't hear the street noise at all.
The only downside was that there is a big extractor fan quite near the window, which was a bit noisy. There were also some noises of people coming after the party at 3 or 4 am. None of this bothered me, but if you are a light sleeper, this place might not be for you. Otherwise, I fully recommend this place!