Well... I probably shouldn't be responding as my electronics are dated and certainly NOT cutting edge:(

fishing with friends that DO have the new cool stuff, however,  I've noticed a few advantages of side imaging technology.  First and foremost, it significantly reduces the time needed to master a landscape.  You can position your boat correctly "first time through" an area.  Example:  with my older technology I need to drive my boat along a weed edge to lay a trail or drop some icons PRIOR to fishing the spot.  With side imaging you know where the weedline/breakline is at all times.  No need to dirve it first.

Same goes for marking the honey.  Yes, you can zig zag around and locate a crib, for example, and drop an icon on it for future use.... but side imaging not only speeds up that process... it will help you find structures you never new existed.

Is it worth the money?  I dunno.  But if given the option, I'd upgrade in a heartbeat.