I got lucky and got a really sweet deal on one of these earlier this year and it has been amazing at what I've found that a) I had no idea was even there and b) would not have picked up on without the structure scan feature. Here are a few screen captures from some of my sonar log files collected with this device.
Here's one image with the signals from the side scan, down scan and regular sonar all displayed simultaneously...I for one would never have understood all the nuances of what I was looking at just from the sonar image....certainly I wouldn't have known about those holes in the base of the rock pile that you can see in the side scan image..

These images lose a fair bit when sized down to fit here but hopefully they'll still convey a bit of what the originals provide.

Another image with all three signals displayed simultaneously...

Another rock pile or something of the sort...

A submerged low head dam....
