Let's be clear on terminology, chugalug. The aircraft you're describing as "bespoke" are of established and proven design, lots of them flying around, readily available spares and predictable purchase cost. On that basis I have no problem with "bespoke". But I just don't buy the line that we face a binary choice between a tortuous modification process and having something designed and built from scratch. To do so for 20 or so Nimrods would have been bonkers. Are some people still living in the days when we ordered aircraft by the thousand, and are our requirements really so unique?