As regards XL318 in the RAFM, it was earmarked for there when retired (having performed the last 617 Sq. Vulcan sortie, on 11 December 1981). It was transported to Hendon in sections and installed there in about February 1982, some months before the Falklands war and XM607's historic mission. Hence it is not really a question of its having been chosen over a more historically significant airframe.