The Rotodyne cruised at 180 kt and had a range of 450 miles - assume that a modern version could do better on range - but not on speed due to the rotor (which provided half the lift in autogyro mode)
So where could you use it? London - Paris you'd be up against the Eurostar and in th erest of Yurop the TGV and similar
Even if it was a lot quieter than the prototype it would still be noisy so you could never run it from a location close to housing - somewhere like Docklands would be OK but then you have to add in the ground transport time v. a city centre to city centre train - and you'd still have modern security checks as well