Drop-in resolution
Ronda 5030.D vs Miyota OS20: do they swap?
Whether the Ronda 5030.D and Miyota OS20 share a case, and what changes if you move between them.
Different footprints. The Ronda 5030.D is 28.00 mm x 4.40 mm and the Miyota OS20 is 30.80 mm x 5.10 mm, so they do not share a case. This is a choice between platforms, not a swap.
The Ronda 5030.D is the reference Swiss quartz chronograph, in a large share of quartz chronographs. The Miyota OS20 is a common low-cost Japanese quartz chronograph module, in analogue quartz chronographs.
They differ in diameter (28.00 mm vs 30.80 mm), height (4.40 mm vs 5.10 mm), calendar layout (chronograph, small seconds at 3, 12h at 6, 30min at 9, date at 4 vs chronograph, three sub-dials, date at 4:30), winding behaviour. A quartz chronograph at 28.00 mm x 4.40 mm with sub-dials at 3, 6 and 9 and date at 4. It is the go-to quartz chrono module; the smaller 5021.D is its bicompax relative, not a drop-in.
Matching diameter and height is necessary but not sufficient. A donor is only a true drop-in when the dial-foot positions, hand-hole sizes, stem length and calendar layout also match. Two movements can share a case and still need a new dial, re-broached hands or a cut-to-length stem.