Hi there,
Hmmm, yea I think he chose the other unit for his use case and testing.(lowest power on the Planet) 
But agree it should be better than what your getting , Something is OFF, I would start with the Transmitter power first try stepping it down and the back up. Also if you have an SDR laying around that would be helpful. LOL same as the $9 dongle for the BLE I now use for everything and couldn’t work without, talk about getting your monies worth. 
What Libraries and BSP 's are you using and maybe some additional info on the DEV environment you have going.
Others will chime in that have a lot of good info here too.
HTH
GL 
PJ 