The only reason the UK looked at the Vark was because the wonderous labour government at the time scrapped the TSR 2, so the Vark wouldn't have come to Britain. As to the TSR 2 I don't know it was designed with the same mission set as the Tornado GR-1 etc. The projected specs for the TSR 2 are actually better than the Tornado better range roughly the same speed on the deck and the advantage there goes to the TSR 2 as it had an internal bomb bay so was flying clean most of the time... As to the Luftwaffe/Marineflieger they where interested in the TSR 2 as well as a host of other countries Australia being one as well. As to the Technology involved I don't see the problem there as it's easier to replace electronic's than to create a new Aircraft...