I have decided to preorder the Lowrance 5200c which is the new replacement for the 3500/3600c units. I have contacted Navionics company and they sent me a sample of thier maps for the Mississippi River. I then bought US Army Corp of Engineers map for the river and it is much more detailed. The map also includes a CD of the paper maps. Question is.....Can I load a couple maps off the chart onto a card for the Lowrance GPS and will it "line up" (for lack of a better word). In other words will the maps position be correct with the lat/long that it is really at?