Re: DSLR or Sony VG-20 ?
 

JVC's prototype uses 4 cards! Supposely each quadrant went to one card. Bad!

I think they are revising the unit so each card has every-other pixel (V & H) so one card is a FullHD proxy. After editing, during export -- if you want 4K2K -- the other cards are used. BUT, part of the re-design may be to support a single card. CF?

Later I'll post the math on a 24MP chips.

The real fun begins with a 36MP chip -- which Sony may have for a Full Frame (FF) camera!