Vacuum: Rubber or Silicon Hose & Plastic lines | Alternatives?

[Bob Weir]

MB uses a variety of vacuum hoses and the vacuum plastic lines are color coded and some have different id.

When they have to be replaced:
1] does the material [plastic rubber silicone matter]?
2] does the id [inside diameter] matter?

Are there any vacuun diagrams on the 124 CD manual and if so, where?

Thanks
Bob