There are no BAD brands of diesel in California -- and I do not think there are any that are markedly superior. It is all pretty good compared to what others find elsewhere in the country.
I try to buy from low-priced stations that seem to sell a lot of diesel (so they get regular deliveries of fresh fuel). The high-priced stations don't sell as much, so their fuel sits in the tanks longer (with the potential of absorbing moisture).
So I recommend buying the cheapest diesel you can find. ARCO, Thrifty, independent stations... it all comes from the same 4 or 5 refineries.