the 179 kung fujas from this year is really crazy soft. about as soft as my hellbent. i flexed the 169 kung fujas which was fairly stiff. the shop didn't have the 189 kung fujas, but damn the 179 one was sexy. with the rocker its the ultimate butter ski.
also the urban punx is probably the softest park ski out there. but you ought to look hard since they stopped makin em 2 yrs ago.