How hard is the rach 3 cadeza tocata?
What a "cadeza tocata" is?
If you refer to Rach 3 cadenza (why do you call it "tocata"?), there are two alternative cadenzas, one written in a "light" and "sparkling" style and another one written in a very "heavy" style with those big chords, jumps, arpeggios... The second one is the one I know better (although I don't play it, I just worked on it) and in my opinion it's very hard, very demanding, technically and physically.