After the success of the 470 series, Marc Fave had developed a new generation of movements for Omega, but rather than buying just movements SSIH group bought Marc Favre and absorbed them into Omega. In 1958 the new calibre 550 series watch launched it might looks similar in terms of design and finish, but was 1mm flatter and has 4 hours more power reserve. The movement stayed in production up to 1969 and experienced several variations during it’s production run including a quick set date feature and day date version. The calibre 550 was design to be an automatic, but a manual wind series was also made known as the calibre:600 series, but thats a story for another day.
Omega sold a lot of watches in this time period and a lot have survived, Some models are more desirable than others and can fetch serious money, but a nice calibre 550 can still be found for a reasonable price.