Omega probably decided to do something to add exclusivity to their brand, when their existing (and extremely good) 3 hand movement was in reality a rebadged ETA 2892, fitted to loads of other watches, mainly a lot cheaper, with spares widely available and capable of being looked after by any competent watchmaker.
So......Advantages
To Omega;
1) Marketing - differentiate the product
2) Novelty, allowing them to continue to charge a premium price
3) "Ownership" of replacement parts market, and the ability to limit reliable servicing to those who have the right tools and expertise, which largely comes down to Omega themselves, or their authorised service agents, although this may be as much about customer perception rather than reality. Tricker to work on than standard swiss lever though.
To the owner:
Moot.
As you might conclude, I'm not a fan although I do have 2 co-axial watches. There are a couple of current models I really like the look of, and I'd be in the market to buy now if they still had conventional movements. As it is, I won't, and my pocket thanks me for it
👍