Both are three-hand, no-chronograph executions in steel, with the octagonal bezel and eight hexagonal screws Gérald Genta designed — but they belong to different caliber generations and solve size in opposite ways.
The Jumbo measures 39mm, the original 1972 proportion, with a deliberately thin case. The Selfwinding grows to 41mm, the size that dominates today's three-hand Royal Oak catalog.
The Jumbo runs Calibre 7121, ultra-thin, with ~55 hours of power reserve — prioritizing minimal case thickness over autonomy. The Selfwinding runs the newer Calibre 4302, with ~70 hours of power reserve: nearly 15 more hours of autonomy in exchange for a thicker case.
Both share 50m of water resistance — enough for splashes, not for confident swimming — and the integrated steel bracelet that has visually defined the entire Royal Oak family since its origin.
If the priority is the ultra-thin proportion truest to the original 1972 design, the Jumbo is the direct choice. If you'd rather have nearly 15 more hours of power reserve and a 41mm case more in line with the current catalog, the Selfwinding delivers that without losing any of the family's visual traits. Neither has verified market price data in Cazador yet.