Choose a sports car instead of a muscle car when the particular sports car gives you the size, control feel, and handling response you want more than the muscle car's engine character, acceleration, or style. The choice makes sense only if its seating, luggage space, comfort, and running costs also fit your life. A lighter or more compact driving experience can be a stronger reason to switch than a faster specification.
These labels are not exclusive technical classes. A muscle car can also be an accomplished sports car, and modern performance versions may have sophisticated brakes, suspension, and tires. Compare the actual models and packages rather than assuming that muscle cars only travel well in a straight line or that every sports car is light and agile.