Originally released in late 2010, this route was one of the first major DLC addon routes for Railworks, TS 2015's early predecessor, and is, in my opinion, the route to which all others have been judged since. So massive in scale was the route at the time, I would say only 2 have surpassed it since, Western Lines of Scotland and WCML over Shap, and both of those were created by the same man, Keith Ross.
Don't expect many of the enhancements that have graced Dovetail Games' flagship simulator since, it was released long before them, but do expect not only a route, but a network, especially north of Carstairs where you not only have passage to Glasgow Central Station through Motherwell with express passenger services but also natural termination of frieght services from the south at Mossend and Coatbridge, amongst others, plus many local services and lines are well catered for aswell. The route is well built and, at the time of release in 2010, was heavily detailed and therefore tested an average PC. The creator, to his credit, edited the route to lessen the load without any detrimental effects on quality.
The detail and quality of this addon is the mainstay of routes released today and the natural upgrade of PC's to run the modern simulator negates any worries of being able to run it.
If you are torn between what route to buy and are put off by the relative age of this route compared to others, don't be, as I said before, this route still stands tall.