Rack and pinion systems are more responsive and have fewer moving parts than steering box with pitman arm systems.

That's correct. Rack and pinion systems are generally more responsive due to their direct mechanical connection to the steering wheel. This system uses a gear-set and is often used in smaller, lighter vehicles because it is simple, reliable, and inexpensive.

On the other hand, a steering box with a pitman arm system is often used in larger, heavier vehicles. This system uses a series of links and arms to turn the wheels. However, it has more moving parts, which can lead to more wear and tear over time.

In terms of responsiveness, the rack and pinion system has an advantage because it provides more immediate feedback from the wheels to the steering wheel. This can make the vehicle feel more agile and responsive to the driver's inputs.

In summary, while both systems have their advantages, a rack and pinion system is generally more responsive and has fewer moving parts than a steering box with a pitman arm system.