There seems to be a 5/6ms difference between the Dude's ping and a ping from the Windows command prompt.
Windows ping reports a steady 21-22ms rtt, Dude reports a steady 15ms.
Any thoughts where the difference is coming from?

Yes sure looks like thatthe difference is minimal.
Sounds like The Dude is more efficient than Windows !!
Here is the code to add to a function;
array_element(ping(device_property("FirstAddress")),0)
You can call the function by name in a probe...