Max stepper motor speed - rpm

I am looking at setting up a CNC router and I am starting to size
components like the ball screw and its pitch along with the stepper
motor speed and torque needed. One question I have is how to determine
the max rpm you can get out of a specific stepper. There are basically
3 parts, the power supply, driver, and motor. Assume that the power
supply is sufficient how do you calculate the max rpm capability from
the driver? Say I start with a Gecko drive that has a freq=200kHz and
it is a 10 micro step drive and the motor os 200 steps per rev. Would
it be 200,000/(200*10)= 100 steps per second. Times it by 60 to get
6,000 RPM. So the drive is capable. Now is the motor. Would you just
have to look at the speed torque curves and see for the desired torque
what speed you can run at? Is there some way to determine this if you
do not know the Mfg of the motor?

My main reason for this question is that I am thinking of buying a
stepper that puts out around 600 Oz-in torque and direct couple it to
my .200" pitch ball screw. This would give me good speed capabilities
when routing on wood. I am trying to avoid to have to add the extra
complexity of a belt system.

Thanks
Scott