I've been looking at the 7i76e.
Mesa 7I76E link
It supports 5 axis, spindle control, spindle encoder, and 48 io ports, all from the built in BOB. Additionally it has two sockets accepting the cables or additional breakout boards.
Also have you considered the integrated servo motors from stepper online? I have some coming next week to replace some nema 34 steppers that lose torque at higher rpm (12mh inductance, bought before I knew better) I'll be using 3:1 reduction with a belt drive instead of the existing direct drive of the nema 34's to increase torque as I don't need 3000 rpm. They were $102 ea., including the servo motor and the motor drive. You just supply a power supply and connect directly to your motion controller like the 7i76e above.
Note, the above with a 3:1 sure reduction would have about 255 oz-in continuous, 500 peak, consistently from 0-1000 rpm with no drop-off in torque with and additional headroom of about 300 rpm with torque drop-off.
Integrated servos
https://www.omc-stepperonline.com/in...p-from[59]
Power Supplies
https://www.omc-stepperonline.com/sw...;400,500,1000]
This combination is relatively simple, not horribly expensive, and should work really well for you with Linux CNC.
Thanks, John Z
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