Waterdog, Mine is equipped with the US basemap. My understanding is that Lake Insight offers more detailed mapping such as depth contours, hot spots, and geographical locations on the lake. In my opinion, I would simply buy the Navionics chip for $100 and plug it into the basemap graph. It would save you $100 from buying Lake Insight and give you more detailed information on your favorite lakes in your area. Hope this helps you a little bit. By the way, I'm lowering my selling price to $950.