This video compares four different ND filters on the Sony FX3 in full sunlight. The comparison is done using the same scene and camera settings for each shot, with all filters set to 6 stops to keep it fair. The four filters compared:
Freewell Bright Day VND filter (6-9 Stops)
NiSi 4 x 5.65" Nano IRND 1.8 Filter
Kase ND64 Clip-In Filter
NiSi Swift True Color VND Kit (1-9 Stops)