EtherCAT vs CAN Open

[zed]

Hello,

I am considering a 2kW single axis application using unistream PLC and unitronics drive and servo motor.  In this application is there any distinct advantage to ECAT over the native CANopen?  The ECAT is an add on module but both support the use of motion function blocks in the PLC, correct?  Does the drive support either protocol natively or are they different drive models?  Any other differences that would lead me to chose using the extra ECAT module?  Is the main difference really just comm speed?

Edit:  Found the answer to the drive protocol question in the manual.  Different models depending on protocol ECAT/CANopen.  Also noticed the drives do not seem to have a STO (safe torque off) function and control power must be applied before mains.

Thanks,