I've fished with a LX5 for years and love the unit. Really didn't think the LX7 could make me switch but I got one to test drive and I'm keeping it. Big LCD screen has great visibilty, Got the horizontal zoom bar on the side that fishes like a Showdown and I can put it exactly where I want it. Big center screen let's me watch the whole water column for shallower fish cruisng thru. Separation is better than LX5. Extremely easy menu system with keys all on the display and all the info you could want along the bottom of the display. One cool feature tells you how much of the bottom the sonar is covering. Also like the depth appearing in the center display so no more guessing or turning the knob from 20 to 40. Used the unit in 10ft and 50ft and it has done the job. Battery life has not been an issue - runs all day and I have power left.
Yes it is spendy but I expect Marcum will soon have an open water transducer available and the LX7 would be a superb unit for your trolling motor.