Hi Zee,
Was a residential electrician/contractor several decades ago. Also in Berkeley. Here is what I would do if I were doing it for myself:
Run 12/3 (#12/3 conductors) metal clad cable (MCC) from the first electrical panel in the house. That 3rd conductor allows you to create what is called a 3-wire circuit. The 2 hot wires share the neutral and allow the loads to cancel each other out. So if say you have 8 amps on one conductor and 5 on the other the neutral will only have a 3 amp load. This reduces voltage drop as it shortens the return path for 5 amps of the load. You have to pay a bit extra for the extra conductor and another circuit breaker but I think it's worth it, especially if you have or ever plan on betting monoblocks, you can put one on each circuit. The MCC provides a metal sheathing around the conductors that is grounded which will prevent any EMI or EMF from radiating from the 120V conductors. Not really sure that this is of any real concern but it gives some peace of mind. I would also install the outlet in a metal box as opposed to plastic for the same reason. Also a metal receptacle plate. And finally I would probably use 15amp circuit breakers as long as the load would permit as this provides a bit of safety for your equipment in the event of a short. I have used Grant Fivis at 650-291-2821 for my most recent electrical work.
You might also consider running another 12/2 cable for any future or present equipment that might be 240V. It would be cheaper to do it all at one time rather than for it to be 2 separate jobs.