Mission Beach and Pacific Beach are two different places. A lot of times tourists ask us to take them to Mission Beach but what they really want is Pacific Beach (or vice versa); and then they end up calling another taxi or walking 40 minutes to get to where they want to go.
Yes, Mission Beach is a great beach and there are a few great spots to grab a drink or burger, but Pacific Beach and North Pacific Beach offer a larger restaurant and bar scene.
Then, to confuse things even more, there's also Mission Bay.
Here are the highlights for Mission Beach, Mission Bay, Pacific Beach (PB), and North Pacific Beach (North PB):