I still use it. It works good. The only thing is sometimes I forget to place the carcard in the same area as the car. Then a search of the boxes that hold the carcards is necessary.
I added extra boxes to help sort out the incoming/outgoing cars at the sorting track on the layout and at the staging yard. Before I ended up putting the cards on the layout while sorting cars.
Like everything you make small adjustments to adapt it to your operations.
I like that it's relatively mindless once you set it up. I operate on a erratic schedule.
It could be flexible when most of your destinations are in staging/future extensions. Simply write up new waybills and adjust the traffic pattern.
Captain of Industry
President of Lancaster Central RR
President of Lancaster & Western Maryland Railway