The interesting fact here is actually that the 139 would have been fit for purpose had it been equipped as promised - it wasn't!
Crab you are right and also wrong. Firstly you were right about CHC/MCA being badly let down by AW/Honeywell's promises and their inability to deliver the correct kit on time.
However, the illumination and AVAD systems which are two of the main problems with the aircraft, were supplied as per the contract. Any SAR pilot/crewman could have told the MOD/MCA that this equipment was unfit for purpose at the very beginning! Is this MOD incompetence or oversight?