If you wanted to be grossly unfair, you might compare BLOODHOUND with a sort of supersonic railway locomotive.
Okay, it has to be said that at this time there may not be a huge market for same. Use BLOODHOUND on the Chiltern Line from Aylesbury to Marylebone and yes, it would do the trip in 2 min 20 secs as opposed to an hour. But there is undeniably the odd downside – such as frying the coaches in the jet and rocket blast, tending to slightly catch up with the trains in front, knocking down half of Harrow and Neasden with the shockwave, and going straight through historic Marylebone station and ending up in Wapping if the brake-chutes fail. Not, let us admit, exactly great sales points.