It should have been a 175 3 car , but a 158 is better then a sprinter. Was the 158 four or two car
A 158 is an express
sprinter. Very, very much better (for regional express services) than a plain old 'Sprinter' (class 150), or even a Turbostar, though.
I think it would be nice to get Swansea served by a regular loco hauled service agains (By the way when did Swansea loose its last regular loco hauled service?, I am sure there used to be a 07:45 Swansea - York crosscountry service which was worked by a class 47 in fact I am sure theres a pic somewhere of it.)
Of course it seems unlikely ATW's mk3's would get the same treatement as Chilterns but I would like to hope so seing as you could have a common pool of mk3's carriages for both operators
I'd hope (given the very long delay introducing mark3s and DVTs at ATW) for power door mark3s too, but because it gives us stock that can be used beyond 2020 not for having a common pool with Chiltern (their refurbishment spec is probably not right for Wales' needs). Sadly, if the ATW mark3s were going to have power doors we would probably have heard about it. In fact, the lack of news regarding mark3s for ATW means I wouldn't be all that supprised if, come September, they just sling another multiple working cable underneath the current mark2 rakes overnight and use them until December.
As for loco-hauled services to/from Swansea, Intercity 125s may have two powered vehicles rather than one, but those powered vehicles do not carry passengers and are essentially locos (though because, unlike the class 91 (very sensible design if you ask me, why do class 90s have two pointy ends?), the class 43s only have a cab at one end I can see why some wouldn't see IC125s in quite the same light as other LHCS).