What is the best portable GPS system for a car? I don't need to play mp3 files with it. Traffic conditions might be helpful. Reliability and ease of use, and one that speaks directions out loud, are important. I can spend up to $800 but don't want something that expensive if something cheaper will do what I need. I want to attach it to windshield, easily removable. I also need something I can readily buy at a store in Denver, since we leave on a 2,000 drive cross country Thursday morning.
