The Studio Polygon 400MMC is an ingame creation of the real life Alexander Dennis Enviro 400MMC on both Alexander Dennis and Scania Chassis. It is available in multiple lengths and has setvars that allow it to be customised to meet the needs of the operator repaints are for.
The model is detailed and is an extremely accurate recreation of the vehicle it is based on. Both the ADL chassis and Scania chassis have their own models, whith different dashboards, rear ends, lengths and more. It looks the part on UK maps, such as Scunthorpe, BoTW and Cotterell.
High definition textures also add to the experience. If you had a wall-sized display to play OMSI on, you'd think you were driving the real thing. They complement the excellent models provided as part of the DLC and really do add to the experience.
The DLC comes with different chassis with different engines and gearboxes: ADL and Scania, with ZF and Voith gearbox options for the ADL variant. These all sound very realistic and it is easy to tell that a lot of time and effort has gone into recording these sounds, as well as sound tuning to ensure that they sound right when you are driving the buses.
The DLC offers multiple length options, for both chassis, like in real life. This means that whatever operator is on the map you are playing, you can make the bus close to how it would be in real life. This adds immensely to the realism when you are using them on UK maps.
Due to the high quality model, brilliant textures and realistic sounds, you feel like you really are on one of the buses and all of the customisation features available through setvars for each repaint (for example, seat models) add to this even more - because you can choose a specification of vehicle for your repaints and when playing in game.
If you like UK buses in OMSI, then this is a must have for you. It makes UK maps that are sent in the present day feel real, especially due to how common these vehicles are in real life. The model, textures and sound all make you feel like you're in the real thing. And, I would say, the DLC is great value for money.