I want to thank everyone for their input and comments, it helped me place an order for a HDS 7 GEN 2. I wasn't to keen on the GPS but had to get it in order to get the larger screen.I may be glad down the road that I got the GPS, will just have to wait and see. Since I have a X 510 c and the transducers are the same ,all I have to do is change out the head unit. The power cable will also work and if I ever decide to upgrade to Structure Scan I will have to change the power cable to an HDS cable inorder to be able to have the yellow wire to activate Structure Scan. Thanks for putting up with all of the questions and especially for all of the help. Hope I made the right decision in going with the HDS 7 over the HDS 5