To change the MAC address I use the common
sudo /System/Library/PrivateFrameworks/Apple80211.framework/Resources/airport -z sudo ifconfig en0 ether xx:xx:xx:xx:xx:xx networksetup -detectnewhardware
It shows the changed MAC address when I run
ifconfig en0 |grep ether
Is this sufficient or should the changed address also appear in System Preferences -> Network and in the extended Wi-Fi details sub menu (alt+click on Wi-Fi symbol)? In both places the original MAC address is still shown although Terminal gives a different address.