I’d love to know where you get the idea that Stadler are awful, their products built for the UK in recent years suggest the exact opposite. And even CAF are capable of building quality when it’s ordered, see the C4K units in Northern Ireland. Northern and TPE asked for cheap so cheap was what they got.
I would love to know where that idea comes from too, as Stadler are the only manufacturer in the last few years to make sure that the doors on their trains opens at the same level of the platform and for the doors that can be used for disability purposes, that an extension comes from the train to bridge the gap between the train and the platform. This is something all manufacturers of trains in the last 10 years should have been doing. Instead, the TOC's and DFT have gone for cheap trains that can be manufactured with reason, quickly with no thought of the passengers and their comfort.
Admittedly, BR did not get it totally right with the HST125 trains and Metro Cammell did not get things totally right with the MK4 coaches. However, there was more time spent on getting the designs of these right than the 4 years taken by Hitachi. There was 5 years between the agreement of British Railways Board to develop a high speed diesel train using conventional technology, to a train running in service. The operational prototype, having been built by 1972 and was tested for three years, before building of the HST trains commenced in 1975. Similarly the building I believe of the class 91 and Mk4 coaches took a similar amount of time.
Yes, the class 800 trains where first in service in 2017. However, if the information I have found is correct the order for the IET trains was placed in 2012 finally, with the first train built in 2014. Now, there may not be as much testing required as the class 8xx units are pretty much based on the class 396 units serving on HS1, just with longer carriages and entry doors at the end of the carriages other than the driving trailers, rather than the positions that the doors can be found on the class 395 units. Although, the announcement of the preference to be an Hitachi train was made in 2009. Part of the issue was down to how much of the GWML would be electrified, when the Intercity Express programme trains came into service, hence why GWR had to change from ordering class 801 units to those being class 800/3 bi-mode trains.
If Hitachi had done more testing as was done with the HST units, class 91 and MK4 coaches, then you would have had a better train. But as has been said in a few threads, it was the DFT running the show in getting the class 8xxx IET units into service, which says it all really.
Now, okay the class 745/755 units where ordered in 2016 and where constructed between 2018 - 2020 based on a design, that has been in use around Europe since 2004. Other than the class 395, there was no other Hitachi trains within Europe and I believe that to still be the case? The UK is the only customer of the A-Train family of trains.
Given the time period Hitachi had to get the trains built and into service, they are pretty good trains to be fair, despite the build quality issues, which I believe would not have occurred had better and longer periods of testing taken place.
I do believe that current market conditions, will prevent the building of anymore IET trains, despite LNER and GWR having options on more trains to be built. I would say that new trains would not be ordered for another two years yet and by which time Hitachi would have changed their bi-mode IET from being Electric-Diesel to be Electric-Battery.