Of course it all depends on airspace, too. Flying around San Francisco, I generally stay below 1500 so I can avoid talking to Norcal. (Why I would I want to do that? - because SFO tower will often give you a transition when you ask them directly, even though Norcal is refusing them).
Thanks for the info, something to remember! Only been through the SFO class B a couple of times and never had a problem with Norcal, but will try your way if and when I need it.
