Hello again. I have had a few PM's seeking more info on the lessons learned on the ducer and sounder, so I thought I would respond to the broader community.
Since I knew we would use this boat as a fishing first vessel, I had the sounder upgraded from the GSD22 to the GSD24, and kept the P79. It was an OK upgrade. I knew the 24 was a better unit, but the ducer just wasn't giving the power and didn't have enough capability to give good returns. Granted I was a bit jaded since I had a dedicated fish finder with Chirp on my previous boat, so I was expecting detail on the screen.
So next step I researched the ducer side. A lessened learned here. I was reluctant to drill a hole in the hull so I looked only at in-hull. The only real options for the GPSMaps 7215 plotter and GSD24 was the P79 and M260. The M265 is Chirp compatible but only works with the GSD26. I am a techie and loved the detail of the fish finders, but the M265/GSD26 upgrade was about $3500 more (the M260 installed was about $1200). The other options would have been a thru-hull tri-ducer to get speed and temp as well. This is what I would have done differently. Get a thru-hull.
All that said, to be honest with myself, and the household CFO, it's likely good enough for what I'm doing now. For salmon fishing just find the bait, and the configuration I have does that.
Now, the other side of the fish finder saga is an external unit near the aft helm. The dual display on the TV works well, but I find myself running inside to flip between charts, split frequency, etc. So I'm looking at a networked 7" unit mounted under the overhang above the aft sink. Or at the very least a plotter only so I can have the topo maps outside and the split frequency inside (because you can see the screens well from the back).
Other area is the 7215 and being limited for true fishing. New plotters support down view/side view and more tranducer options. If you are looking for a fishing first vessel with a Ranger, i would look to upgrade as much as possible in the build with Ranger. But of course, it's only money 🙂.
I hope this helps! And more than happy to have an excuse to go fishing, so if you are local and want a first hand look, I am in Edmonds
Cheers,
Chris