I have a HDS 7 GEN 2. I am thinking about Structure Scan. This will cost about $600. I can buy a new Elite 7 HDI for $700. The unit is interchangeable with the HDS 7 power. .The hst-wsbl transducer on the back will show 83/200 and by changing out the hst-wsbl on the front I can have down scan on the trolling motor. I am not a big side scan man, could be wrong. I am not sure I would get that much from Structure Scan...... at least not $600 bucks worth The new Gen 2 Touch will show down scan by using the down scan transducer.......Am I overlooking something???? Please comment, And thanks. How much is my HDS 7 unit worth??? Works perfect and has GPS.