[Russ_Boston]

Slow down yes. But that doesn't mean that a head-on crash at 14MPH is safe. The
damage from a collision happens because of the kinetic energy that must be dissipated. Kinetic energy is proportional to the square of the velocity, so when a cart stops from an initial speed of 20 mph it has more than twice as much energy to dissipate as there would be if the cart were traveling 14 mph. (20^2 divided by 16^2 = 2.04 - this assumes the mass of the carts are the same). That energy has to go somewhere when the cart stops.

Sealt belts for me. I'll risk the rollover entrapment issue!