One further question - has anyone switched from a GS to an RT and then gone back to a GS or do folk stick to RTs generally?
I have gone RT - GS - RT - GS. It really is what you use it for.
If doing miles on a motorway to get to a place then the RT is the best because when you get their it will still hustle on the back roads. If you intend doing back roads all the time with occasional Motorway or Autoroute then the GS.
This is all IMHO.