[AZ Traveler]

You will still get the "data was not complete-proceed with caution" even after updating the software - it is just telling you the info for a particular area is not great. While an aftermarket unit may not give you the warning the data all basically comes from the same source - its just not telling you so. An RV GPS can help keep you out of trouble with bridges and other obstructions but they are not foolproof. If you plan to stick to main roads you can probably get by without it although the east coast in general is tougher to get around in with an RV.