I agree with the Garmin mediocre support.
I bought a boat with a 162C chart-plotter in perfect working order. As I had to move (sail) the boat 80 miles to her new harbor I opted to buy Trip and Waypoint Manager so I could lay-out my trip in the comfort of my home while it was snowing outside. I thought TWM would have a detailed chart which it doesn't so I needed to buy Mapsource Blue Chart Americas according to Garmin support.
I did so and unlocked my charting area where I will be sailing and planned my first sail trip with this "new" boat laying out my course.
Then when it was time to synchronize with my boat chart-plotter it would not transfer my chart which I paid $175 for to the Garmin. Many calls later I still don't have a current updated chart on my Garmin resulting that some of my waypoint show to be on land instead of water.
If I would have known it wouldn't work i would not have bought 2 software programs and a external power supply and connection wire set as for $100 more I could have had a new color chart-plotter/GPS.