dually question? new springs ????

[wahl4m]

just got a 83 chevy c-30 with a hodges car hauler bed /rear springs seem to be worn out ,it sits on the overloads-empty ! i would like to replace the springs-the std replacements are a 9{1} =10,3955 # springs ,the hd versions are 4650 # springs -same amount of leafs ! about a $100.00 more for the hd versions ! has anybody out there done a hd swap ? is it worth the money difference ? {both springs have the same arch }any ideas ?thanks mike