Good steering servos are one of the most overlooked hop-ups, in RC touring cars. Yet it's very important.
It's the difference of being able to countersteer through a chicane, or not.
Take a look at this Hitec HS-525BB
Speed 4.8/6.0v : 0.17 / 0.13 second
Torque 4.8/6.0v : 46 / 57 oz. 3.3 / 4.1 kg
Torque wise, you get around 10 oz / 1 kg extra, with 6 volt BEC. And the speed is quite interesting too.
Personally, I find a servo cant be fast enough.
The good thing about buying good steering servo / ESC's with 6 volt, is that they can be taken to the next car. So it's an investment, which last much longer than most other equipment in this hobby.
A good bang for the buck ESC, is the DuraTrax IntelliSpeed 8T Pro Racing Forward ESC
. Actually, it's a rebadge Novak TC2. It goes for 80$ at tower.