Having been diagnosed with a life-threatening allergy to pies in my youth, I have never flown MPA.
I do believe that ASW is important. However, having watched the procurement and force-structure merry-go-round for many years, I can't over-emphasize the importance of a community having a consistent story to tell the people who sign the cheques, particularly if they're pushing for the Mercedes-Benz (if not the Maybach) solution and there are people peddling Toyotas or Citroens.
And I don't recall (even in PPrune threads) being told that avoiding detection is a reason for high-altitude ASW, until the last few days. Indeed, I think there have been a few people insisting that the P-8A is too super-good at low altitude.
But if counter-detection is important, then what's the spec? What are the standards? Are there any? Because I would be willing to bet that a little C295 with modern six-blade props has one heck of a lot different signature from the P-3 with those four-paddle-blade things. And the Treasury is not interested in anecdotes.