a SJ will be more fun, but an a/m will be even more fun then an SJ.
I know you said that prior to OP saying hes already tasted the aftermarket waters, but that's about as subjective as it gets.
I would just look for any year superjet with a 701 and a b-pipe that's propped right. Bonus points for dual carb motors, ada head, and other bolt on goodies. Even a clean 650 ski if the pickins are slim and you want something now. Superjets hold value well.
Test ride it and if it rips and the price is right take it home. You'll spend your season with a sh*t eating grin as you put the hours on it