this is measured in ms. so the higher the number the more latency you will have. The manual says use 5.5ms only for high end digital and that 11ms will work with most digital. 11ms is the default so that is a safe setting. You could try 5.5 and then compare the two. From the documentation it would appear some digital servos can not handle the faster response time. I don't have the DX3R but this is what I gather from the manual.