Which Software?

Hello All,

I have the milling machine sorted out, the servo motors, and the
drivers, but the software is baffeling. I see most software venders
explaining how it works with stepper motors, not servo motors and
that's what is confusing. Please correct my assumption that the
software will drive either type motor depending on the motor driver?
Looks like the feedback from the motor encoder 'regulates' the step
and feed rate - now how does the computer know if there is an under
or over drive - as if open loop, or does the feedback input into the
computer - closed loop?

Also need a recommendation on the software - something worthy of
spending hundreds for.

Thanks much up front,

Bill C.