3D/2D side-scan sonars

 
  Hey all,
  I just spent lunch time trolling through a bunch of YT's on the 3-D sonars (Lowrance and Hummingbird)and watching the side scan aspect of them.  Do any of you use the side scan from your kayaks?  The transducers look like there at least 3X as big as the little puck I have in my outback for my Eagle Cuda 250.  I guess if you have one of those long transducers its not kept inside the hull in a water bath.
  The displays on the these 3-d sonars are unreal.  I'm wondering if the side scan feature, the 3-d aspect and the great under water pictures these things give, have really helped any of you land fish?  I can see that the restriction my little FF has now compared to these new modern sonars.  Yes my 250 (With GPS) shows the bottom contour and depth (Right below my hull) and it does display the water temp as measured from inside the hull) and as of recent fish & chill it did show there were fish!  I remember using the FF on Loch Lomond lake (Here in Santa Cruz Co.)back when we were able to kayak it, and seeing fish and even a thermocline line on it once. 
   I'd like to have a new sonar, but won't be able to justify it to the CFO (Wife) as the one I have work fine.(For what it was designed to do)

The structure scan & 3d are there to help find the structure the fish will be associated with.  Yes, the side LR 3d transducers are late @ around 11" long.  Not very conducive to kayaks but I have seen a few with this type of system.  You are correct; no in Hull water-bath for those.  As for 3D, that is very new to the civilian market and will only get better over time.  In short, we witnessed the birth of true 3D this year.