for ability, peak and sheer footballing genius R9 >>> cr7
CR7 wins with longevity but that's really it.
I'm afraid Cristiano is out of his depth here as far as football ability is concerned.
It's not a contest between the two imo, as pre injury R9 is much better at everything related to football except for in the air where CR is indeed fantastic. R9 is a much better dribbler, passer and technician as a whole, he's much better in tight spaces as he needs less leg room to operate compared to CR, has a lighter first touch and is a hell lot more press resistant.
Add a sharper finisher to that. CR to all his goals misses a hell lot of chances, while comparing the number of goals between eras is pointless:
Inter scored 62 goals in 97/98, out of which R9 accounted for 40%
Barca scored 102 goals in 96/97, out of which R9 accounted for 34%
Real scored 121 goals in 11/12, out of which CR accounted for 38%
In 14/15 we scored 118 goals, CR had 40%
But the gap in the quality of the goals is big, that's where the difference for me comes from. R9 made better plays, scored better and more difficult goals