The 121 has to be done alongside the Class 117 which were both Pressed Steel products. Doing both together is essential for the sake of efficiency. Furthermore, they already have a home on DLOGW where they can be used to correctly sideline the 101 which were not prototypical on Thames Valley services in the early 1970s with only a few 101s in the fleet up until retirement in the early 1990s. I believe that even Classes 103 and 104 outnumbered 101s in the area for two decades or more (103s not so long).
Agree. The 121 doesn’t really fit on any current TSW route apart from (maybe) winter services on the St Ives branch. A 117 would be more useful and could double up as a 118 if we got a DLOGW2 for the forthcoming Devon Banks route.
Perhaps the Class 118 could also be done in parallel to classes 117 and 121. They were built to identical design with 118s being made by BRCW as opposed to Pressed Steel probably due to a lack of capacity at the latter. This way we would get a further 3 classes of first generation dmu in one go.
