This video suggests running to Cardiff in summer rather than May.
Great shots, and I think they look absolutely fantastic there, so modern and shiny alongside the tatty fading green decor of Central station. The white and red is really smart.
They seem fairly well received anyway, apart from I noted a heavily biased video made by a YouTube rail review account called “Midland London,” which gave a somewhat one sided rant about TfW “ruining their express services.” Not a very balanced representation of the trains at all. Other than that, they seem to have gone down quite well.