Whats your opinion on SD cards
I am planning on purchasing an sd card if it will give me additional valuable information that I dont already get with my Lowrance LMS-522C and I think it will. I have some pretty good detail such as the river channel, and water depths in 10 feet increments. I am looking to be able to see more things like creek channels and contour lines etc. Would like some testimonials on what you are using , brand it is, and how you like it. I have looked at 2 different types and will be needing one for Tennesse's Middle Tn lakes. Thanks