Entering service in 1999, the British Rail MPV is a CargoSprinter train that is used for track maintenance on the majority Britain's railways. Most of these MPVs operate as semi-permanently coupled pairs, carrying the equipment neccessary to keep Britain's railways running. The majority of the MPV fleet carry tanks that can spray either water, weed killer, de icer and sandite onto the tracks to prevent problems from arising due to vegetation and ice. Some used on HS1 and the West Coast Main Line carry cable drums and work platforms for cantenery work. During 2005, there was a trial that used an MPV for light freight services. This train carried a single containerised timber carrying module, a water tank to act as ballast, and 7 OTA wagons between the pair of MPV units. Another unique variant is the switches and crossings train.
These things are a common sight on the Medway Valley line and usually live at the yard just east of Tonbridge. They're also known as Multi Problematic Vehicles due to their tendency to break down and go wrong. Would be interesting to see in TS being so unique.
There's only me that's crackers enough to bring the MPV to train simulation https://www.facebook.com/goldstartrains
They have been available in TSC for ages and super duper updated version 2 of the MPV is in the pipeline for release shortly. https://alanthomsonsim.com/