This is very nice. For range testing i connect one device to my computer and run this script on it:
import meshtastic
import time
interface = meshtastic.StreamInterface()
while 1:
str = time.strftime("%a, %H:%M:%S", time.gmtime())
interface.sendText(str)
time.sleep(60)
Each minute i get a notification on the device i bring on my walk. It is easy to see when you get out of range. So far i have only been 1 km out and had no missed messages.