I'm pleased that Scania are offering a 9 litre engine with their E400 chassis but I wonder whether Arriva would pull their fingers out if the Cummins units on the X15 and X18 start playing up? What Arriva could do in a few year if they wanted to upgrade the X10 / X11 is this:

- 7522 to 7528 to Blyth for X10 / X11.
- 7529 to 7533 refurbished to Sapphire spec and joining the above.
- 7501 and 7502 to Blyth acting as spares.
- 15 new Sapphire spec Scania Euro 6 MMC's to Ashington for the X21 / X22 joined by a further 2 new spares in Max spec and corporate livery.
- 10 new Max + Scania Euro 6 MMC's to Ashington for the X15 / X18 joined by a further spare in normal Max spec and corporate livery. Max + would basically be Sapphire but with no Audio announcements due to the long distances and Max branding.