Actual dimensions and weights would be interesting to compare with current 710s and GEs in the 4500-5000 hp range .
The link on the other thread (by JMT) gives a drawing of the SD90MAC fitted with the QSK 95.
The hood is much taller than the original to allow for the aftertreatment equipment above the engine, but the engine itself (not meeting emission requirements) is both shorter and lower than a 16-710G3 or a 265 H engine.
While Metrolink are talking about using the QSK 95, GO Transit in Toronto are fitting TWO QSK60s, 5400 HP total, instead although they initially proposed to use the QSK 95 in place of the 16-710 G3B in their MP40 locomotives.
A single QSK 60 is fitted in the lower powered CBH locomotives built by Motive Power, with a QSK 78 in the higher powered units.
A quick check of CM3301 in Goulburn would show how big those engines are, and as lower powered versions of the same engine family, would give an idea of reliability.