The 420 has been used for scholastic and college sailing since the early 1970s. The earlier generation boats were very light with bendy rigs and an ability to sail with the mast stepped forward as a cat rig or aft with a jib in a sloop rig. Boats were fast and exciting but very fragile. With repetitive use they quickly became maintenance nightmares. Eventually boat builders added more glass and resin to keep the fragile hulls from breaking and converted over to a much stiffer untapered spar.
This iteration remains popular to this day but has many drawbacks. More glass and resin makes the boat much heavier, slower and non-responsive to subtle changes in trim. Not only have the boats become so heavy that they are glued to the water in lighter winds but also they are very difficult to move around without an army to help lift and carry them. Furthermore, a single skin boat is prone to failure along the flanges where the various molded pieces are bonded together.
By using modern resin and various thicknesses of coring material Whitecap Composites has made the Turbo 420 much lighter than the current versions, much more durable, so maintenance is dramatically reduced, and replacement is on a considerably longer timeline. Value is dramatically increased at the expense of weight and bored sailors.