I'm also in downtown SF. Pine and Front and speeds have been horrible and inconsistent.  My speeds at home (Near GG park/Cole) have been worse. Used to be great, but the last 3 months I average about 400kbps down/ 30 kbps up.  Not very good for a major metropolitan city .  Here's my earlier post regarding SF coverage. I responded to another post. The more people posting and and spreading the word, the quicker it should get resolved (hopefully)

https://community.verizonwireless.com/message/986525#986525