Mirrorless form factor brought lighter devices... With the modern sensor tecnologies, grain/noise is under control, high resolution target is now at least on 6K video with no overheating... And price range starts today under $2000 for S5II/S5IIX at the active cooling side... : D See Blackmagic customers in the bargain on their turn, even them can also become FF users nowadays... Long story short? The fastest lenses.