All in-n-outs are privately owned, they raise their own beef, and process it all the way through, and it is never frozen. They pay their employees better than any other fastfood, managers make a ton too, and you can tell in the service and quality. More businesses should follow their model.
Taste is subjective to each person, but the business model rocks it!
We have a sonic in Apple Valley and it just plain sucks. In and Out is the best chain burger and fries you are gonna get out here. Try the fries animal (grilled onions and cheese) style no (thousand island) spread.
There is one in OC and also in Ventura. Not seen any in the LA metro area. A couple of years back there were lots of Sonic commercials on TV. Thought it was weird as they had no restaurants in the region. I guess they had some kind of advertising package which covered this region.
There was a Sonic in Azusa, but it's gone. Their locater shows one in Duarte, Anaheim, Santa Ana, Lancaster, & Rancho Cucamonga. I've eaten there a couple of times. I know some people think they're amazing. I thought it wasn't bad, but it didn't stand out to me.