Stepper motors have limitations on speed and accuracy. Speed is a
>function of the maximum steps per second the motor (and driver) can
>do.
Jeez, folks... all one needs to do is look back some years at the line printers that were around. They were controlled by stepper motors, as well as by both linear and rotary optical encoders, and they had some fairly good accuracy.
For heavier applications like machine tool bed transitions, sure the task will be more difficult, but still quite doable.
Cincinnati Milacron, as well as any good Japanese CNC machine tool maker achieves 10,000th inch accuracies EVERY DAY! Guess what their drive mechanisms are?