New Machine Build Anyone running two Gecko drives off same BOB port?

I am working towards a cnc machine with a rotary axis, which would total 5 drives (y axis has two rack and pinion's, one x axis, one z axis, and one rotary axis).
Is anyone running a combo board ( 4 axis from Campbell Designs) and driving two gecko G203v's off the y axis opto's?
The gecko's have 2.5ma current draw so I would imagine as long as the current sink of the combo board has sufficient amperage this should not be a problem. Therefore I could save the A axis for the rotary...

Thanks,
Andy