Some interesting input here chaps. Maybe, at the moment there is little or no direct military use for this beastie, however, that's not to say there never will be. Also spinoffs from development, could well find their way into future Mil. Projects. Did Concorde not benefit from reheat, surely a product of military research ? I also like the statement that basically, if no one gives it a go, no one will and we may miss a new phase of development. It all looks a bit Fireball XL5 to me, but then, as Danny42C says, "you'd never get me up in one of them things".
OK Venus ? OK Steve.
Smudge