I used the 3 main ones over the past years.
1. Verizon ADSL: Up to 1.5MB, best latency, 1st choice if available. Many reports of problems lately, but not sure if they apply to SD area.
2. Aster Cable: 512KB down (only very expensive biz-plans beyond that), aweful latency (above 500ms), many outages that affected only internet service but not TV and therefore took forever to get repaired (5+ days on average).
4. Telecable: What I use now. 1.5MB down, average latency (100 to 250ms), upspeed advertised as 128KB but getting 400KB. So far I only had short outages that lasted 1 minute max. Speeds can go down the drain on weekends and holidays (from 1.5MB to 0.5MB in my case). Telecable is also the only ISP where I am sure they throttle speeds on most ports except 21, 80 and a few others. Can get around it by setting programs to use non-throttled ports.