3 years = two generations, from the perspective of computers. I would never sign up for something that long. 18 months is considered a generation cycle; things change fast. Only you can decide what is at risk, how much of it you want to manage yourselves, and what the service provider offers that is of value to you, of  course.

I keep multiple computers available, so if something happens, I can switch to another. I do a triple storage routine for safekeeping my working files: mirrored to two computers, saved to a usb device and also copied to the cloud.