What is the latency of the MTx/MTi or MTi-G?

Please refer to the User Manual of your product. You will find relevant information under 'Communication Timing'. Please note that the processing time can depend on the firmware version you are using. Please make sure that you are using the latest version of the MT SDK and refer to the documentation that is installed on your computer with the MT SDK:
<Windows Start menu => All Programs\Xsens\Documentation\>