You will quickly find that you need to figure out a way to organize these lists if you have a lot of files.
One obvious way is to organize the lists the way you have your Mapsource folders organized - assuming you are happy with that.
I see Daryl organizes things by date.
I organize mine first by type of ride - DS or Single Track and then by location first by state or multi-state big rides and then by region especially for New Mexico.
This organization really works well for me in BC. I can click on a state/region list and see all the rides for that state or region.