I may be late to the party and everyone else is using this already - but I recently changed my PC based route planner to the Web Based
My RouteApp (Gold) Cost about €72 for three years.
I use TomTom 410 on the bike but find route planning so much easier on the Laptop. With this APP you can use Google Maps, Street map or TomTom Maps - If you use TomTom maps they will exactly match the one in your TomTom Sat nav' so no more dodgy way points. It also allows you to go to street view to check out the road you think you might use to see if its suitable. (I lead a lot of Club rides and have to make sure I don't take them down too many roads with grass in teh middle

). Also while you are planning its easy to switch between maps to find details on the ground like cafes and garages etc. If you are riding in a group and other members have TOM Toms and also the app its easy to share routes as its all web based. Also you get a choice of what type of file you want to save the route as - I prefer .GPX as it saves the route as a track rather than a series of way points and you can "Bluetooth" .GPX files from the 410 to other TomToms.
As I say I may be late to the party and you are already using it - It also has a phone app but I find that too small to be really useful.
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