Got ahold of a Casio fx-991ex and CG-50 to match my Classpad II. I'm really impressed with them but there is something about the fx-991ex... (see comments) : r/calculators
Using Memory In calculation with CASIO fx-991EX fx-570EX CLASSSWIZ Calculator - YouTube
CASIO Scientific Calculator FX-991ex Classwiz Original – CBPBOOK