I lived and worked-by-remote here for over a month with my partner. The apartment is pretty enormous for city living, with plenty of room to unpack. Wifi is fast and the unit (including the kitchen) comes equipped with pretty much anything one would need. John responded within minutes (sometimes seconds!) on the few occasions I texted a question.
Also, the Marina is one of the most beautiful neighborhoods in San Francisco... there's a postcard-worthy view of the Bay and Golden Gate Bridge from the sidewalk in front of the building.
Highly recommended!