It all depends on your vehicle(s). I like mine to have enough length that I can sit on the ends without it affecting the handling. My pair and team reins have extra length so I can drive any of our team vehicles without needing new reins. Safety and personal preference.
yes i prefer a little longer reins also, as i like to sit on them. i also have large minis which leaves mini reins out except with my 2 wheel cart. i think mini reins are 10 feet long and i bought 12 ft.