I would get a locker.
Either one is a good choice, but as long as you wheel w/another 4x4 you should be able to get yourself out of most any situation with a strap.
San Diego here too.
There is a decent sized SD crew for offroading, we make several trips year round. We mostly post on yotatech.com in trail planning section. Check it out.
I'll go up to big bear as long as all the 4x4's are gonna run some of the trails. Plus I should be able to drag along the rest of the SD crew.
It's gotta be worth the time spent taking off my stock set of rims/tires for the offroad ones :)