ViTrains 37s don't really need flushglazing, they really NEED their standard glazing fitting properly! The entire cab glazing, front windows and cab sides are cast as one unit, that doesn't fit very well - if you remove the side windows, and then cut out the three front windows and take care to fit them properly, the result is really rather good. If memory serves, the internal body moulding around where the horns intrude into the cab stops the glazing unit fitting properly.
Best not to get me started on how badly formed the holes on the body of ViTrains 37s are to receive their respective detailing pieces. That said, they *look* like 37s when they'e finished, and if you ditch the traction tyres, they run extremely well too, and are *much* easier to do a quality sound fit to than the Bachmann model.
On balance, regarding the effort needed to get the 37 looking good on the rails, and good though they are, I'd have trouble recommending anyone spending any more than 40 quid on one.
I do rather like 37s... A mate of mine that has a good part of my fleet on loan on his layout stopped counting at twenty....
-Rob