It's an RC Helo site, but the logic applies to other areas of the hobby as well.
https://www.rchelicopterfun.com/rc-servos.html
"...digital servos have much improved deadband, better resolution, faster response, quicker and smoother acceleration/deceleration, and immensely better holding power.
You can test this very easily by plugging in a digital servo and an analog servo to your receiver. Try to turn the servo wheel off center on the analog RC servo.
Notice how you will be able to move it slightly before the servo starts to respond and resist the force - it feels a bit "spongy".
Now do the same thing with the digital RC servo. It feels like the servo wheel and shaft are glued to the case – it responds that fast and holds that well."
However, do note that digital servos require more input power relative to output power, when compared to Analog:
"Yup, digital servos are power hungry. All those hundreds (thousands) of power pulses per second use up more battery power than an analog servo would. This really is not that much of a problem these days since RX battery packs have at least double or triple the capacity of what the same size/weight pack had just a few years ago. That said, it can be a big issue for your BEC (internal or external) or a voltage regulator all of which have a finite maximum current output. "
Since RC cars/trucks generally only need one servo doing the hard work (steering servo), digital makes sense as it's still usually well within a BECs output to power them, until you start getting into high end models, or want to up the voltage to increase torque output
Conversely, for my RC planes I used to to strike a balance: I use analog for more basic functions (eg. flaps and landing gear), where generally the servo is simply traveling from point A to B, and precision or response time isn't that critical, but efficient power output, and lower cost, are. For my main controls (especially the all-important elevator), digital is the way to go.
More recently though, as digital servos take over the hobby, it sometimes makes more sense to just go digital all around, and beef up the BEC if needed.
.I did notice the HW60bl esc provided smoother operation of my analog servo than the Traxxas XL 5hv
