Pro/cons to either. Slding doors are usually more energy efficient, don't take up any real estate inside or out, but narrow opening, rollers can be an ongoing maintenance item.
French open wide, need space inside or out depending on the swing(can't place furniture in the opening).
If opening to a screened porch, no problem, but to the open air, screens are usually needed, can be a headache sometimes. Swinging screen doors usually fewer issues than rollers.