Sonic Drive-in does not exist at this address in Monrovia. I drove to this exact address and it is an industrial park, never has there been a Sonic at this location. The telephone number is not Sonic's also. I really love their food, great selection to choose from for a fast food place. Too bad there aren't more in Southern California. Believe me, if it was there, I'd know about it!
Pros: Order from your car, no pressure, nobody waiting behind you.
Cons: Only 1 in LA/Orange County