German fotomagazin did test RF 70-200mm F2.8L IS USM vs. NIKKOR Z 70–200 mm 1:2,8 VR S in its latest issue 11/2020.
Overal score:
5 of 5 stars for both
optics:
95 vs. 91 of 100
mechanical built:
90 vs. 100 of 100
Optically the RF wins in resolution, vignetting and distortion, esp. wide open up to f/5.6 with only more distortion @70mm.
Mechanically the RF loses some points because of plastic barrel (but it saves weight) smaller focus ring (but it is smaller) and little bit worse flare protection.
Overal score:
5 of 5 stars for both
optics:
95 vs. 91 of 100
mechanical built:
90 vs. 100 of 100
Optically the RF wins in resolution, vignetting and distortion, esp. wide open up to f/5.6 with only more distortion @70mm.
Mechanically the RF loses some points because of plastic barrel (but it saves weight) smaller focus ring (but it is smaller) and little bit worse flare protection.