There is another style of double solenoid valve that is spring centered. The center position can be either all ports blocked or the cylinder port open to exhaust. The all ports blocked is useful if you want to be able to stop the cylinder in a intermediate position. You do have to make provision to be able to dump the cylinder pressure with the one vent valve.
With the two position double solenoid valves, it is best keep one solenoid energized. Otherwise if the valve is bumped just right, it can shift by itself. The power draw the energized valve is minimal.
We tend to use single solenoid valves unless we have a reason to use a double. The advantage of the double is that the disabled state will not effect the position of the cylinder. There is a brief disable during the transition from autonomous to teleop where this can be important.