Hi there, gen the omega has a few issues that need to be addressed , such as cam belt and tensioners, every 40,000/4 years and oil coolers failing, but this is due to the incorrect anti freeze levels and poor servicing. Cam cover gaskets fail due to blocked breathers as a result of poor/irregular oil changes and lack of servicing again. Front camber issues tend to scrub out the inside of the front tyres so keep an eye on this as well. IT IS NOT TRACKING SO DONT BE FOBED OFF BY TYRE FITTERS. IT IS A CAMBER PROBLEM AND CAN BE ADJUSTED.
As long as you change the fuel filter and air filter then you need not use addatives of any kind.
keep on top of the servicing and use gen vx parts your car will give you miles of enjoyment
I have a 2.5 tourer as well so enjoy it mate.