Edge 705 GPS: Highs and Lows

I've been using the Garmin Edge 705 GPS down here in North Carolina for the past few days on some rides. As I'm here to do basically nothing but ride, I've had loads of time to play with the device, trying to get it to do what I want it to do.

Here's how things would work in an ideal world. First, I would design a route for the day in DeLorme Topo USA 7.0. The route would be completely defined on known roads, and give me an idea of where the tricky climbs and turns would be. Then, I would take the route that I carefully drafted in Topo, and send it to the Edge 705. The Edge 705 would, in turn, let me know where the major climbs are, and where the tricky turns are, using its internal routing.

I've managed to shoehorn my desired functionality, almost. My original idea was to export the route as a DeLorme .GPL file, use GPSbabel to convert it to a GPX file, and send that to the device. I even used the filtering feature of GPSbabel in an attempt to limit the complexity and size of the GPX files I generated. However, for routes with over 100 or so track points, the Edge 705 would, after a while, choke with a cryptic error message: “Route Waypoint Memory Full.” It then crashed. It's running firmware 2.10, and I hope this gets better soon!

I've had better luck using GPX2CRS on the generated GPX file, turning it into a Garmin course file (.CRS), and sending it to my device using the Garmin Training Center application. This will give me a bright purple trail on the map screen that I can follow, and will let me know where the climbs are. However, I'm leery to use this method for a couple of reasons. Firstly, the Garmin USB Storage API still does weird things with course files. Where do they live, and how many of them can I have on the device? I'd like to have on the order of 100 different routes, all on the device, easily backed up, without having to worry about some arbitrary storage limitation. Garmin's Edge GPS devices seem to be hybrid devices: part traditional GPS, part strange undocumented API. Garmin, are you listening? I'd like to know how and why course files and their management are different!

My real goal is to use this thing on Intercity. That's 220 miles of riding. I haven't been able to get the entire Intercity route onto the Edge 705 without it choking somehow. Thumbs down.