This is very nice to know for anyone local, or someone visiting San Diego for a few days.
If you are in the Downtown area just swing by for a quick visit to experience this Supercharger and get 12 kWh of electricity in 10 minutes of being plugged in, then leave before your 15 minutes are up. For a Model S or X that is about 36 miles of charge, for a Model 3 it should be close to 48 miles of charge.
I would not make a special trip for this, but if I find myself downtown and have 15 minutes to explore, then I will take advantage of it to explore this new Supercharger.