Buy used. People upgrade constantly and used are cheap as new outsourced and undercuts the old. Entry level graphs now are nicer than top of the line graphs not even 10 years ago? And the only major difference is screen size at a certain point, which for a kayak is easy. 1 until not two, don't need GPS, and even a elite 4dsi looks more like a 7 when it is basically a handheld unit for you. As close as it is on the console, a larger unit is more a hindrance to movement hogging space and extra weight to carry is always a detractor.