I am glad you mentioned that point.pedanticmongrel wrote:On top of this, it's the only route I know which has loads (and i mean loads) of AI traffic in the quick drive mode,
The say timing is everything and if you are looking for a route with an absolute boat load of prototypical QD AI, then the latest release of the ECML update by DP Simulation is now available:
http://dpsimulation.blogspot.co.uk/2014 ... t-v13.html
And given the list of routes that are mentioned in the OP, then this would seem to be ideal, and free.
And in direct answer to the OP, with all the money this will save you, the two UK routes I would go for if you are able to, would be the WCMLoS route (Shap) and/or the South London Network route.
Do not be put off also, as I was in all honestly, by those strange and nasty 'foreign' railways. If you fancy a change from driving on the correct side of the formation, I would take a look at the German Garmisch route. I adore it and it has opened a whole new 'avenue of pleasure' for me in a TS sense that is.
Hope this helps,