John's place was super charming, and much larger than I could have hoped for from a Parisian apartment. The location on the Canal St-Martin was awesome, with plenty of excellent bistros, bars, cafés, and boulangeries/pâtisseries in the immediate vicinity. At night, the neighborhood picks up, and you can spend hours engaged in conversation over wine with a friend while sitting on the canal amongst the multitudes of hipsters and college students who inhabit the area. The République, Jacques Bonsergent, and Gare de l'Est metro stops are all within a reasonable walking distance. Be prepared for stairs (the apartment is on the 5th floor, no elevator), but it really wasn't a problem for us even with luggage.
From booking to check-out, John was a great communicator. His instructions for getting into the apartment and using the wifi were clear, and he helped us by arranging to have the building's doorman hold our luggage between our early morning arrival in Paris and the afternoon check-in time. There was some confusion about the date we would be arriving, so the apartment wasn't ready for us at the stated check-in time, but John was very attentive to our messages and he rectified the situation as soon as he could.
Aside from the minor hiccup at the beginning, we had a great stay!