"Control" is not the same thing as Customizing the GUI.

While I will concede that I cannot customize the interface, I know Control4 is not going to start changing the interface every 6 months. I know that if it is changing, I will have a heads up, and I know that if a major change does occur, existing systems can absolutely stay right where they are at and not be forced to update. When OS 2.6 came out a few years ago, Even though the ap did not change dramatically, C4 still took the route of creating a new app rather than force everyone to update. I still have plenty of systems in the field happily running 2.5.3 (And earlier even) that felt zero impact when Control4 came out with new software. Heck, I just updated a system yesterday that was still running 1.7.4 with Embernet Zigbee devices and V2 Remotes.

Similar boat with Savant.. who, even though they did play musical GUI for a couple years, did not force folks to update their app. I still have a system out there running version 4 software with Logitech Squeezboxes providing audio. that hasnt been supported in years... But it still works.