Use the Diagnostics display in the Tools menu to see a count of audio dropouts as well as total MIDI events in or out. Use this during a stress test. If you see the audio dropout counter incrementing, its a sign that something in the system is choking occasionally. This many not always be a big deal. It depends upon when the dropouts occur and your own particular usage.
The diagnostic display also includes a count of MIDI output errors for use with EHCo. If you suspect not all EHCo data is being transmitted correctly, the error counts can indicate errors returned from the MIDI output port driver.