For my uses DSI should be just fine. I generally only fish 2 lakes (both electric-only reservoirs in the 800 t0 1,200 acre range) and neither is over 35-feet deep in the main channels. I also troll for crappie a LOT more often than I shoot jigs. trolling in 10 to 25 feet of water, a front/TM mounted DSI unit makes the most sense because when I see structure that looks enticing I can simply mark the point and continue on course so that my jigs will run across/through it. If I get bites, I can swing around and make another pass and re-observe the structure. If it still looks good and/or I hook up again, I simply mark it as a waypoint. Over time I should be able to develop some VERY good trolling routes on these 2 lakes. Plus, when bass fishing (my primary favorite) I fish for BIG bass only. They tend to stay at isolated deep-water, off-shore structure that is almost impossible to detect with 2-D. Most of the other Big-Bass chasers I know swear by the DSI units for our particular style/type of fishing. And unlike many people, I don't have to de-program my brain from interpreting 2-D junk because I have never used a fishfinder of ANY kind in my entire life until a couple of seasons ago (largely because I never owned a boat until then. I've been a devout farm-pond guy for many decades but unfortunately the decent farm ponds are becoming quite rare and due to the direction our legal system has gone, fewer and fewer folks will allow people to fish them anymore). For big water fishing the side scan may be the best way to go, but for my intended purposes I think the DSI will work just fine (And I hope to be able to verify that within the next few weekends!!!).