They also give more precise movement, which is required for precision 3D flight. They do use more battery power because there is signal being sent to them all the time. Analog servos only have signal input when they are being moved. Frankly, digital servos are not really needed for everyday "boring holes in the sky" flight. They are essential for precision fllight of any kind. Unless you intend to do precision 3D or pattern I personally don't think digital servos are worth the extra money. Maybe your money would be better spent in buying a 6 volt battery. Just my opinion.

Regards,
doubledee