The roll is definitely a better bike for a bigger rider. My main concern about the 820 is the rear wheel - it has the old-style 'freewheel' hub - the freewheel (ratchet) mechanism that lets you coast is a separate part that is screwed on to the hub, and there is along section of unsupported axle that makes damage very likely. The Roll has a modern 'Freehub' design hub - the freewheel mechanism is part of the hub and the bearings are out at the end of the axle on both sides. This is a much better design for bigger riders.