In fact, it is a default factory option for the ADL E500s to
have Ventura doors... It's like Bode is the default supplier for
the doors of the Citaros.
ADL E500s used to be fitted with Deans, before switching over to
Ventura when Deans stopped production. If it is necessary due to
operational needs, SMRT may request for ADL to fit Masats doors as
they have much faster opening and closing times for their sliding
plug doors compared to Ventura.
Also, MB is no longer using doors from Bode for their Citaro C2
as they switched to an in-house design to save weight.