I swim for exercise. I have tried riding a bicycle, power walking and jogging. For me, swimming is MUCH better. Not only am I using muscles from all over my body, rather than just legs or arms, but I feel much better when I swim. Swimming clears my mind, so any stress that I may have when I get in the water is gone when I get out. My energy level when I am not swimming is high and I have noticed that, at least for me, it pumps endorphins. As a result, my overall mood has generally improved.
So yes, give it a try. You will not be disappointed