I have an old CraftRobo at work. It takes in vector images and trawls them for lines of two particular colours (programmable, default red for cutting, green for scoring.) These lined are in the image but are not printed.
It is cute to watch it cutting away, but I have not yet thought of a way to get it to cut parts out of pre-printed models, or even third-party vector-format files. It is designed to be used with files that are created for it. I have not yet examined the Pepakura option, that might well be fun.
In addition to the blades (which I have found to be quite hardy), an adhesive backing sheet is needed to retain the work under the blade. In my case, this quickly wore out and I lost one project that slipped out of alignment. I have one spare backing sheet, but have not yet found a source for replacements.