The 350AR has a packet radio port. I wanted to read more on this, since I believe the 350R did not have this capability. I think you can use the packet port to gain access to the TNC, hopefully in KISS mode, which some of the popular APRS programs out for the PC will support. Unfortunately, I could not download the AR manual.
XASTIR is an open source APRS program that runs on OSX, among other places. You should be able to get your GPS talking to the PC, running XASTIR, talking to the packet port on the 350AR.
You should get the GPS for the 350AR - it will be much easier to use as a self-contained unit as opposed to dragging the PC around everywhere. Use the PC when you need to display other stations around you.
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