I'm in NZ and have CBus lighting interfaced with control4.
Also happen to be an electrician, cbus approved installer and control 4 tech ( in my last job). If it's just lighting then cbus will be rock solid and as a product it's been around for 30 years. Imho the moment you want to add AV devices, security systems etc it becomes very limited and expensive.
So far as integration goes it's simple; CBus installer does their programming then passes a list with every light/switch and the group address of each to the control4 integrator who will installer either rs232 communications or IP interface - then installs drivers and binds each one to the group address of each light.
Suggest you look for a control4 dealer who also does cbus and you shouldn't have an issue.
I personally prefer cbus lighting because-
if power fails all lights will return to the last state when power is restored without any intervention
if you move house you can leave the cbus stand alone and take control4 to your new home