i've never gone 80 ft, but i've done 20'+ regularily. it's a sprocket drive. and i've never had any real issues with running the 20' lenghts before. however, if it is many color foils, maybe limit it to 10', "just incase", then you only lose 10' at a time!
one thing i will mention, is make sure all the little teeth on the roller (both edge & envision) are clean before you start long runs. take an exacto knife and pick off all the sticky residue left behind from previous runs. i get buildup on mine every few months, and keeping that clean is the best way to ensure it stays on track.