have booked 3 weeks holidays in september, but yet to book flights, wondering whether to book the flight to san francisco or los angeles, i intend visiting both anyway and maybe las vegas or san diego, los angeles would probably be more convenient for this, but something tells me i would like san francisco better, so maybe might spend most time there, the flights are only good value if i book a return flight to either city rather than two one way tickets to and from both cities, any ideas...