Thanks for all of your replies.
It seems common sense that if the pumps are still functioning in good condition 20,000fhs after being fitted, there is no point in replacing them. Interesting story regarding FR HiTemp, I am actaully looking at how you weigh up which technologies to insert into future fuel systems for a university final year project. (I have a s/w model and am doing a case study on engine feed pumps)
Coming from a systems design background, components will always be designed with an expected service life in mind, and I can understand FR Hi Temp's concern in the situation described. However, as Jettison Valve has shown, these are at best a good guide!