Both skis tend to lose camber and stiffness as you ride them, just like any other ski really. The stepups seem to do it just a bit faster than chrons though. Plus step ups are heavier and tend to delam easier. I'd say go chrons but that's just my $0.02
Chronics, they're a lot of fun. Supposedly they have the same flex thought right? ANd besides actualy weight, how heavy it feels has to do with it's pop and swingweight characteristics. A heavy ski can feel light if it has a ton of pop.