Hi,
these modern servos pack in so much stuff, you'll be blown away once you get the software running.
In some respects you are making life more difficult for yourself with the analogue CSMIO controller, you now have the drive closing the acceleration
and velocity loops with the CSMIO closing the position loop. With a step/direction controller the entire servo loop is closed by the drive and a number
of control features come into play which cannot happen with control split over the drive and CSMIO. I refer to indexing position and/or speed.
My Allen Bradley servo allows you to select two control modes, say step/direction position mode and analogue velocity mode, either of which can be selected
by asserting one digital input. Really handy, assert one input and my servo turns from a free running voltage controlled motor to a high torque indexable
servo with a resolution of 5 arc min.
Anyway the chances are these servos will be in the family for many years and no doubt you will get to sample how they do with an open loop step/direction control.
Craig