I am a system76 owner. The sys76 driver installs a ppa in your repositories, so as long as you update your system it should also be updated (I believe we are now in version 3.0.x). If you downloaded the deb file from their website and installed it then you have the drivers running. In case of doubt you can always open them and click in restore defaults, which will bring the drivers to the same config as to when you bought your machine.This is also the procedure when you perform a fresh ubuntu install or upgrade in your system.
You can open your dash and type system76. If you see a black sys76 logo then you have the drivers installed.
Other than that syst76 drivers works just fine and are transparent to the user. They only had a small incompatibility with Ubuntu tweak, but I reported the bug to UTweak devs and they fixed it.
enjoy your sys76 beauty !!