Jim, after many years of just buying the base models of FF's, I bought a boat that had two map-enabled Humminbird units.
My prior fishing has always been shallow-water oriented. I used the cheap FF's simply as depth gauges. Now, I am fishing in deeper locations, and need to know more about what slopes; ledges; and bottom configurations that I frequent. I also have to find my way back to the dock in a maze of islands and cuts.
First, I added the Navionics ($10.00 per year) app onto my phone. I also went to their website and spent time looking at the free web app. The data on the app and the website are exactly the same. The issue with the phone app is that I can't see it in the sunlight. The web app is great, but I can't take it with me.
I recently bought a chip for one of my new-to-me GPS quipped fishfinders. It was at the helm and I loved it for getting to these new places. I could finally see the depth contours; structure and old roads, bridges etc. I also could duplicate my route to find my way home.
THEN, I found that if I wanted to actually fish over some old bridge, I needed the information at the front of the boat, where my trolling motor controls were. And, a few days ago, I bought ANOTHER chip for the front station.
I can't say that I have caught any additional fish with the two chips, but I sure know more about where/what I am fishing over.
At $150.00 per chip, given that they cover both TN and TX for me, I think I'll get my use out of them.
It all depends on how you use the chips, and whether or not you even need them. The one time the new chip found the channel route to get me home I thought it was worth it. I might have looked for 30 minutes if I didn't have the tracking route on my new toy.
rich