I have an iPhone 5 with Verizon postpaid contract plan [unfortunately].
The data speeds have been miserable last several months. Most of the time, my download is less than 1mbps and upload will be like 30kbps.
Right now, I am near the city hall area and my speeds are 0.03mbps down and 0.03mbps up. and yesterday was 0.04mpbs down and 0.10mbps up.
I went to the verizon store and it works fast inside since they have repeaters in the store. They said the phone appears to work fine and said it depends on the area..blah..blah..basically they just stopped short of admitting their network sucks in SF.
I'm extremely disappointed with the service considering how much they are charging me for it.
I think Verizon should give a discount or let us terminate the contract without the Early Termination Fee. I would be happy to go back to AT&T. They have much faster speeds here and lower fees. 
Anyone else having such slow speeds in SF? Feel free to share it here..