A rank 3 6* elsa is 3140 atk, a r4 is 3593. Seeing as this elsa is only level 1/25 are we going assume 7* are rank 4 equivalents?
all i know is no way i'd even bother is a R1 7* is equal to a 6* R3. so i hope what you guys are saying is true and it'll be more like equivalent to a R4 or R5.