The movement still has to fit the watch
Dial feet, hand sizes, stem height, calendar position, case dimensions and complication layout all matter. A similar-looking movement is not automatically interchangeable.
Replacement and overhaul are different services
If we recommend a movement replacement, the estimate should say so plainly. We do not call a swap a complete movement overhaul.
Sometimes keeping the original movement matters more
Vintage, collectible and sentimental watches may justify preserving the original movement even when replacement would be cheaper.
Some watches are especially well suited to movement replacement
Common fashion, quartz and workhorse automatic watches can often be restored economically through a correct replacement movement and careful casing.