MRH 90 IS off the shelf - it is 99.?% common to the German TTH.
The delays in service acceptance and certification have been due in part to immaturity in the supply chain caused by having multiple versions being developed concurrently; a few technical issues which may be acceptable to other operators but are not to us, e.g. floor rating, rear ramp, ground clearance; and technical issues which are somewhat (but not wholly) unique to Australian operating conditions and requirements, e.g. cracking windscreens, door gun position.
What has also been discovered and which wasn't fully appreciated when the aircraft was ordered, is its unsuitability for conducting assault landings in dusty/dry environments where brown-outs can occur. This is the domain of the Black Hawk due to its tailwheel configuration and long-stroke main oleos!
So, in summary, as a pure point to point transport or maritime helo, the MRH is a ripper, and when mature, I'm sure will provide sterling and reliable service to the ADF. But if we want to maintain the battlefield assault capability, a small side order of UH-60Ms might be worth considering...