ok, i happen to know a thing or two about both these ski, so let me shed some light:
-98mm waist, which is about the breaking point from park/ allmnt ski to Pow/Big mnt ski, as far as dimensions go. its gonna give you alot more float than your TM's and gonna be a decent bit stiffer...
-THC stande foe Triple Hybrid Core, which is a combination of Microcell, Isocell and wood to create the flex pattern.
-i personally would choose these cuz in my opinoin, wider is better, except on say...urban, or if your a park rat..
-its what i would choose
The Rossi S3
-Solid waist for East coast skiing
-The wood core is gonna give you a softer flex, which will allow easy ollies, easier to float in pwder then a stiff ski of simailar dimensions
-Looks like a fun ski from what i have seen...
hope that helped