Based on my experience it doesn't matter, class 4 is fine that is what I am using. What does matter very slightly is if you delete any unnecessary files like support for different screen resolutions, including inside zip files like data.zip.
How long does it take for your iGO to load? My WinCE iGO 2.4 takes ~30 seconds to load not including whatever it takes to acquire the satellites.
Bookmarks