S7's are the resort rental pow ski, you can throw a beginner on em and they will have fun. As for real chargers. My dad skied em in some fresh in utah and didn't like them at all, super deflective, sloppy, unpredictable. I'd call it an entry level directional pow ski. Super 7's are meh, better. Rossi seems to finally be doing something right with the Squad 7's, they look burly.
These are two 100% different skis regardless, one is a directional more traditional ski, and the other is a jib pow ski. Both will excel in deeper soft snow but will still be useable when it firms up. How much do you weigh? Where do you ski? What type of terrain do you like to ski? Are you going to be spinning, landing switch? What type of skis have you like in the past? Would you consider your self intermediate, advanced, expert?