HiTec digital servos are nothing short of AWESOME! I've used KO, Futaba, Multiplex, JR, and Airtronics, and in my opinion HiTec is by far the best. I use HiTec digital servos in every single car I own, they are the best servos I have ever owned.
The HiTec HS5925MG is in my opinion the best servo on the market. It's got all the speed you could want with enough torque to operate the brakes of my 1/5 scale car, I use it for the steering and throttle servo in all of my cars (except for 1/5 and 1/12 steering)