There is no need to worry about hopping aboard a fast moving rocket on your next dive because these typically move pretty slowly. On the lower end of the price, the scale is the designs that can only reach top speeds of about 2 miles per hour. Users like these because not only are they generally more affordable, but they can be used by first time divers that aren’t quite all that familiar with the equipment. On the higher end of the price scale are designs that can reach top speeds of about 7 miles per hour, and these designs can typically travel just a little bit deeper than some of the slower designs.