Help Before I Purchase ODrive

Hi! I’m pretty familiar with using steppers in projects but I’m a noob with brushless servos. I have a stepper project that is too damn loud and would like to replace my motors with servos. I have some small NEMA23 industrial brushless servo motors with both an internal hall effect encoder and optical encoders on the shaft. The label gives these specs:

Continuous Torque: 38.00 OZ-IN
Continuous Current: 5.35 AMP
Rated Voltage: 60 VDC
Speed: 5000 RPM

My application is driving a screw at nowhere near the constant torque spec let alone the max and with little holding force. I care most about speed and as quiet as possible.

(1) Because the motor is rated at 60v should I necessarily buy the 56v drive or would the 24v version suffice for my application? What is the effect of underdriving? Speed or Power loss?

(2) I understand that optical encoders are much more precise than hall effect encoders but it appears that both were connected in the motor’s original application. Why might that be and if there is a good reason for that does ODrive support that reason?

Thanks so much in advance for your advice. I’m eager to learn about servos but don’t want to be immediately frustrated by buying the wrong driver.