I use NROUTE, it came with my garmin gps. I use use a laptop in my truck and it works great. I don't think there is any limit to the amount of stops you can enter. You get a visual of all stops so a lot of times the visual works better then the auto routing. I plug a tape adaptor in to the head phone jack of the laptop and into the trucks stereo, that way i get all audio directions thru the truck's stero. Also google earth offers a subscription for routing as well that works with garmin products. good luck.
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