I apologize, i should've been more clear.
The LX7's; once you join them to your WiFi network, you can utilize GCC via network to control, adjust settings, push schedule, base hardware changes (fan/temp/HO/HE/PBT)etc. this is only possible on the LX7's due to the additional WiFi chipsets that are not on the LX6 platform.
The LX6's(and LX7's) can be added to and controlled by a ProfiLux controller via the PLM-PWC add-on card.
In this case, you will connect to your ProfiLux controller and simply make Illumination channel changes, and push to the light.
However for base hardware changes, such as fan, temp, HO/HE Output mode, you will still need to connect to the light direct via USB.
As for the difference between LX6/LX7 the cluster upgrades will get you the UV channel, but as you mentioned PBT, WiFi, any additional efficiency/power benefits are chassis functions of the LX7's and will not be established by the cluster upgrades.