You'd have a lower risk of heart disease and, from what they say, just about everything else. You'd look better. You'd grow rich and famous. Running is boring. Aerobics is for people who own leotards.
Swimming is for fish.
You just can't find an exercise that suits you. It's anything but boring, and you don't need a leotard. And you won't find a tuna doing the tango. Here's why you should have the next dance. As with any exercise, your degree of cardiovascular fitness will depend upon how long, how often, and how vigorously you dance.