One nuance which I would offer up for consideration - with ever more advanced line aircraft (CH47F, MH60M, AH64E etc) which are glass cockpit and quite expensive to fly, you need a light twin trainer that can prepare crews for that environment.
If that light twin is able to be close enough to the line aircraft that it is able to significantly reduce the amount of transition hours flown on those advanced platforms before a pilot is operationally ready, then that becomes part of the business case in favour of the more advanced trainer.