The Trio systems have all the features of the Duo, crisp, clean, accurate, and simple to use with all that's needed included: instructions and demos on a DVD, marking out tools, stops and guides to hold your board. All the Trios are equipped with calibrated parallelograms which make repeated projects and marking out even simpler, this might be of particular interest to photographers who tend to have several images of the same size. 

However the Maxi has a further twist in having twin parallelograms, which make long projects, such as panoramic windows easier still, but also allows smaller work to be accommodated at one end of the system, as easy to use as a smaller system.