I went to BPS today to look at new Elite 7HDI. I was impressed, great unit. I have read on this forum that two transducers are needed. Not true - 2D and DI are from the same transducer. This is Lowrance's first sonar to have regular sonar and down scan in the same unit( w/o Structure Scan). The salesman told me I didn't want to mount it on my trolling motor as I would have to be going at least 4 to 6 miles an hour to get a good picture with down scan. Also said my HDS 7 Gen 2 would get a much better picture with Structure Scan ( was this a sales ploy????). I liked the Elite 7 HDI and feel it would be better for my type of fishing. Would someone familar with both units please speak up or correct any statements I may have made in error. I respect this board and what the guys on it have to say. Thanks.