I'd second Bazz - mixing might be a good idea, out to LAX and back from SFO. Even when dates are restricted for advance upgrades, I've never had an issue getting a mileage upgrade at SFO even before the new cabin layout with extra suites. And you are avoiding the Oracle nightmare in late September, which would likely chew up all seats on planes, rooms in hotels, reservations in restaurants ... These days, there is a good chance you will be able to upgrade ahead of time, even if the availability is not there at the moment.
It boils down to whether you want to fly at good times (I'd love to be able to catch a later flight, 6:30 to 7pm, out of SFO), or want the full VS experience. A leisurely lunch in the SFO clubhouse, like many of these folks have already stated, is one of the nicest perks of flying UC out of SFO.