I agree, RAN and the ADF are wedded to ESSM. The Kiwis seemed primarily interested in CAMM. The Canadians are also a ESSM development partner and user. But had no problems installing CAMM for the Kiwis.
ESSM is a great missile, but it is bigger and heavier and more expensive. With bigger, heavier more expensive launchers. CAMM seems like a fairly easy missile to integrate, the Canadians seemed to be able to do it. I wonder with ASMD if it had a loadout of CAMM would that be enough to allow a CIWS to be fitted.
It would also be a bit of a mismatch.. The ASMD radar is the ideal partner with ESSM. Not sure how its advantages would go with CAMM.
Interesting. I wonder if that will change going forward with the CSC builds etc.
If the ASMD upgrade had included both the Sea Ceptor missile, AND removal and replacement of the Mk 41 VLS, then going with 32 Sea Ceptor missiles in a cold launch VLS, plus a CIWS might have been a possibility. However, given a choice between 32 air defence missiles with a range of 50 km vs. 32 shorter ranged air defence missiles plus a CIWS with a max effective range <2km... I would rather be able to hit an aerial threat further away, as that gives more opportunities to re-engage should initial intercept shots miss.
Also, given that it seems the RNZN upgrade retained the CIWS, replaced the radars with newer systems and removed the Mk 41 VLS (which could be quad packed with Sea Ceptor) in favour of a smaller/lighter VLS with cells for 20 Sea Ceptor it might mean that the displacement of the Mk 15 CIWS, positioned atop the hangar roof, might not have left enough topweight margin for 32 missiles even of the smaller Sea Ceptor. In that case, I would definitely prefer 32 ESSM vs. 20 Sea Ceptor plus CIWS.
As for the radar, I would imagine that the CEAFAR radar panels would work just fine with Sea Ceptor as well, the part which would make a difference would be the CEA MOUNT illuminator which the ESSM requires while Sea Ceptor, using a different type of guidance, does not require illumination.