Mitch, I haven’t run one myself so I’ll let someone else tell you about their experience with the side imaging units, but I have heard a lot of good things about them. Here’s a little piece of new info that I can share. Last season, they only had the super-sized SI units, but this season they have come out with the 5-inch unit, which cost much less of course.
Humminbird 797C SI
We just recently got our first shipment. It looks like they’ll run about $950, less than half of what the 900 series cost last season.