Just curious ... how is it better? Dh and I have the 305. He upgraded to ... I think the 500 and decided it wasn't worth the extra money. It actually may have been the 705, I'm not sure now. Anyway, he only used it briefly and went back to the 305, which is pretty shocking since he usually has to have the latest and greatest of everything. He "intended" to sell the newer one on eBay, but apparently lost it!
Anywho, I'm just curious what's miles better about the 500 than the 305. As for mapping and/or finding a gas station, etc., we have an iPhone for the rare times we need that, but you don't even use the mapping.