I have made the same mistake that you have made. I purchased the Toughcase two weeks ago and tested it out last week. It simply is not made for geocaching. I wrote on an article by lincoln adams on geocaching with the ipod + dual about my experience with the toughcase. He was reviewing it and we both came to the same conclusion: the toughcase is simply not a handheld gps made for geocaching. Here is the article
http://www.habitationofjustice.com/magellan-toughcase-review-what-you-need-to-know
If you have a better experience PLEASE let me know. I am trying my hardest not to get a refund for the product. I am displeased with groundspeak for advertising a GPS that simply isn’t a GPS.