One Word............Fantastic. I have the Vista myself and the Mapsource Topo is an exellent deal. It gives great detail and is easy to upload your tracks for the day on the computer. The detail is just as good as a map showing elevations and contour. It's also great to check out area's on your computer through topo and make notes then transfer them to your unit. Look on eBay for a much better price than retail.