Just want to clarify some stuff here on the Nuvi 350 interface using Gtrans etc.
The Nuvi 350 is the ONLY gps that will work. This is either due to a bug in other gps units or a beneficial bug in the Nuvi 350.
What happens with most of the others, if they work at all, is the waypoints from APRS stations don't MOVE when a new reported location for that APRS station comes in. It simply adds another one. So you will end up with a million duplicate stations in there.
The Nuvi 350 moves them properly. It is too bad since the Nuvi 350 uses the old style low sensitivity gps chipsets, and for the best performance you should run an external antenna. A bigger nicer unit would be nice as well. But nothing to be done!
So basically, yes you need a 350, nothing else will do. GL!