I was really impressed with the graphic quality of G-Trax Berkshire and for $16 a real bargain. So I dropped my current project and started a simple scenario on the default Monument / Castle Rock route, just to see it perform. For those interested in the development process I have put a scenario download at https://download.yousendit.com/cmcwUGhaTlFBNkZjR0E9PQ
I will periodically update this as the scenario develops and perhaps if you are interested in starting to develop your own scenarios you can leave questions here. As the scenario changes I will add additional links. Of course you will have to purchase the loco, but for $16 US I don't think you can go wrong.