SATS,
Don't tell me that the RAF/RN never looked at the bottom line. I would hope that looking for the best kit, which may well not be the most costly, should rule the day.
As for the RAF 'perfecting' SAR, well now we are OK all we need is some clapped out old seakings and we are there. You should bear in mind that nothing is prefect, just as nothing is ever good enough. Everything in life evolves and hopefully for the better.