They require an H1-B visa now to do rotations? News to me.
Norcal was taken off the list when I started, but it sounds like they're bringing it back? Can't help you with that since it's so new. As for Socal, I have a friend in LA for his rotations and he's liking it so far, except for the lack of OR time during the surgery rotation.
AZ sites? It depends. I'm technically West Valley and most of my sites are in the West Valley, but I do have a few East Valley and Tucson sites. They do try and respect your wishes and keep you in the region you request, but that doesn't mean you'll have everything in your particular region. My drive times have been anywhere from 5 to 60 minutes depending on location and traffic at the time of my commute. Also, keep in mind you will have to be one month of rural rotations.