Mike,
In response to your PM, I have used the TomTom Navigator before and was pretty impressed, understanding why most have given it excellent reviews. However, I stuck with Mapopolis because I prefer their mapping style/interface. It does remember your last several locations so you can backtrack or recalculate the route, and it does integrate with your PDA's contacts. However, if I recall correctly, you have to use a 'middle-man program' to go from Navigator to your contact/address book, and back again. It's a little awkward, but not a big problem. Aside from that and 'average' tech support, the TomTom Navigator is a great GPS system and would make a fine addition to your Palm.
Hope this helps,
John

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